Initial import miette-5.9.0 am: 0694d0de18 am: 5f60651017 am: 30582e8f5a am: 639dbdf126 am: f65d43dce7

Original change: https://android-review.googlesource.com/c/platform/external/rust/crates/miette/+/2638950 Change-Id: Id5387f32905dad695d5df34020e0d79801ca945f Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
author: Matthew Maurer <mmaurer@google.com> 2023-06-27 00:15:42 +0000
committer: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com> 2023-06-27 00:15:42 +0000
commit: b89e57f0a8c2e009aa6145b1a9bbe5f5baef3a34 (patch)
tree: 4e2459aa3960ec4d7332844de024ea249f394b4f
parent: b11879fb7d28d05b2bf4422962504020dc7745e9 (diff)
parent: f65d43dce7f4462d83a52b909fb2d07f1f10ad6e (diff)
download: miette-b89e57f0a8c2e009aa6145b1a9bbe5f5baef3a34.tar.gz
46 files changed, 9682 insertions, 0 deletions
diff --git a/.cargo_vcs_info.json b/.cargo_vcs_info.json
new file mode 100644
index 0000000..dea8a89
--- /dev/null
+++ b/.cargo_vcs_info.json
@@ -0,0 +1,6 @@
+{
+  "git": {
+    "sha1": "91e5f5b7e347b921921bac7135c56c600abb1fab"
+  },
+  "path_in_vcs": ""
+}
+\ No newline at end of file
diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 0000000..9fa8b51
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,7 @@
+# top-most EditorConfig file
+root = true
+
+# Unix-style newlines with a newline ending every file
+[*]
+end_of_line = lf
+insert_final_newline = true
diff --git a/.github/FUNDING.yml b/.github/FUNDING.yml
new file mode 100644
index 0000000..001724f
--- /dev/null
+++ b/.github/FUNDING.yml
@@ -0,0 +1,12 @@
+# These are supported funding model platforms
+
+github: [zkat]
+patreon: # Replace with a single Patreon username
+open_collective: # Replace with a single Open Collective username
+ko_fi: # Replace with a single Ko-fi username
+tidelift: # Replace with a single Tidelift platform-name/package-name e.g., npm/babel
+community_bridge: # Replace with a single Community Bridge project-name e.g., cloud-foundry
+liberapay: # Replace with a single Liberapay username
+issuehunt: # Replace with a single IssueHunt username
+otechie: # Replace with a single Otechie username
+custom: # Replace with up to 4 custom sponsorship URLs e.g., ['link1', 'link2']
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..4fafac3
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,87 @@
+name: CI
+
+on: [push, pull_request]
+
+env:
+  RUSTFLAGS: -Dwarnings
+
+jobs:
+  fmt_and_docs:
+    name: Check fmt & build docs
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v1
+      - name: Install Rust
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: stable
+          components: rustfmt
+          override: true
+      - name: rustfmt
+        run: cargo fmt --all -- --check
+      - name: docs
+        run: cargo doc --no-deps
+
+  build_and_test:
+    name: Build & Test
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        rust: [1.56.0, stable]
+        os: [ubuntu-latest, macOS-latest, windows-latest]
+
+    steps:
+      - uses: actions/checkout@v1
+      - name: Install Rust
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: ${{ matrix.rust }}
+          components: clippy
+          override: true
+      - name: Clippy
+        run: cargo clippy --all -- -D warnings
+      - name: Run tests
+        if: matrix.rust == 'stable'
+        run: cargo test --all --verbose --features fancy
+      - name: Run tests
+        if: matrix.rust == '1.56.0'
+        run: cargo test --all --verbose --features fancy no-format-args-capture
+
+  miri:
+    name: Miri
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v1
+      - name: Install Rust
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: nightly
+          components: miri,rust-src
+          override: true
+      - name: Run tests with miri
+        env:
+          MIRIFLAGS: -Zmiri-disable-isolation -Zmiri-strict-provenance
+        run: cargo miri test --all --verbose --features fancy
+
+  minimal_versions:
+    name: Minimal versions check
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macOS-latest, windows-latest]
+
+    steps:
+      - uses: actions/checkout@v1
+      - name: Install Rust
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: nightly
+          override: true
+      - name: Run minimal version build
+        run: cargo build -Z minimal-versions --all-features
+
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..5784075
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,17 @@
+/target
+# Generated by Cargo
+# will have compiled files and executables
+debug/
+target/
+
+# Remove Cargo.lock from gitignore if creating an executable, leave it for libraries
+# More information here https://doc.rust-lang.org/cargo/guide/cargo-toml-vs-cargo-lock.html
+Cargo.lock
+
+# These are backup files generated by rustfmt
+**/*.rs.bk
+
+# MSVC Windows builds of rustc generate these, which store debugging information
+*.pdb
+
+/.vscode
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..0b842de
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,919 @@
+# `miette` Release Changelog
+
+<a name="5.9.0"></a>
+## 5.9.0 (2023-05-18)
+
+### Features
+
+* **serde:** Add `serde` support (#264) ([c25676cb](https://github.com/zkat/miette/commit/c25676cb1f4266c2607836e6359f15b9cbd8637e))
+* **const:** Constify various functions (#263) ([46adb3bc](https://github.com/zkat/miette/commit/46adb3bc6aa6518d82a4187b34c56e287922136f))
+* **nested:** Render inner diagnostics (#170) ([aefe3237](https://github.com/zkat/miette/commit/aefe323780bda4e60feb44bb96ee98634ad677ad))
+
+### Bug Fixes
+
+* **misc:** Correct some typos (#255) ([675f3411](https://github.com/zkat/miette/commit/675f3411e33d5fae86d4018c3b72f751a4c4bc2f))
+
+<a name="5.8.0"></a>
+## 5.8.0 (2023-04-18)
+
+### Features
+
+* **source:** Add getter for NamedSource name (#252) ([be3b2547](https://github.com/zkat/miette/commit/be3b25475147e92fae631b510c8de22949eada45))
+
+### Bug Fixes
+
+* **narrated:** put URLs in their own line ([adbff65e](https://github.com/zkat/miette/commit/adbff65e4ed52103569a3a5cd09c1bee79f8e361))
+
+<a name="5.7.0"></a>
+## 5.7.0 (2023-04-01)
+
+While this is a semver-minor release, there's potential for it to have
+knock-on effects due to the syn2 upgrade. There's been issues as this new
+version propagates between syn/thiserror versions (for example, see [a similar
+change in eyre](https://github.com/yaahc/eyre/pull/92)).
+
+The other thing of note is that backtrace printing is now **much** better! Try
+the hook and see for yourself!
+
+### Features
+
+* **deps:** update to syn2 (#247) ([a2157205](https://github.com/zkat/miette/commit/a215720576fbda249138808f3469017d81eda9f0))
+* **panic:** improved backtrace handling ([b0453215](https://github.com/zkat/miette/commit/b0453215f62318bedeb4af1cb00dcefbb739d619))
+
+### Bug Fixes
+
+* **colors:** change unicode to default to ansi (#249) ([159f2b35](https://github.com/zkat/miette/commit/159f2b354b7ea83f842a58be98c45d0175b1faad))
+* **tests:** disable doctest that doesn't work with default feature flags (#248) ([0b445dc2](https://github.com/zkat/miette/commit/0b445dc2b4b30d40f03defc130bfa3e7396b51d4))
+
+<a name="5.6.0"></a>
+## 5.6.0 (2023-03-14)
+
+### Bug Fixes
+
+* **ci:** configure clippy-specific MSRV ([b658fc02](https://github.com/zkat/miette/commit/b658fc020b23b0715339c5c60f7c12c947f9a747))
+* **graphical:** Fix wrong severity of related errors (#234) ([3497508a](https://github.com/zkat/miette/commit/3497508aa9b8d8503d7aae997738a4323408ffa0))
+* **atty:** Switch out `atty` for `is-terminal` (#229) ([443d240f](https://github.com/zkat/miette/commit/443d240f49e9f48756ee88e4cdc377f09d44454e))
+
+### Features
+
+* **protocol:** implement `Ord` for `Severity` (#240) ([ed486c95](https://github.com/zkat/miette/commit/ed486c959d8e8fbd4247af7d47d7e32c8a88321d))
+
+<a name="5.5.0"></a>
+## 5.5.0 (2022-11-24)
+
+### Features
+
+* **SourceCode:** Implement SourceCode for Vec<u8> (#216) ([c857595e](https://github.com/zkat/miette/commit/c857595e1ae689028c5c5b66148e81b175eaa509))
+
+### Bug Fixes
+
+* **derive:** elide lifetimes in derived functions (#226) ([c88f0b5a](https://github.com/zkat/miette/commit/c88f0b5aa0786a0f4bb778686548f91db96ea6af))
+* **graphical:** Fix panic with span extending past end of line (#221) ([8b56d277](https://github.com/zkat/miette/commit/8b56d277ef476438a1c7383c29f6c1a0a1684818))
+* **license:** fix mangled license text to improve recognition ([d5fbb340](https://github.com/zkat/miette/commit/d5fbb3409c7cc950c502eb77578d5f1062384fb5))
+
+<a name="5.4.1"></a>
+## 5.4.1 (2022-10-28)
+
+### Bug Fixes
+
+* **graphical:** Fix panic with zero-width span at end of line (#204) ([b8810ee3](https://github.com/zkat/miette/commit/b8810ee3d8aee7d7723e081616dd4f2fe8748abe))
+
+<a name="5.4.0"></a>
+## 5.4.0 (2022-10-25)
+
+### Features
+
+* **version:** declare minimum supported rust version at 1.56.0 (#209) ([ac02a124](https://github.com/zkat/miette/commit/ac02a1242b1d6452a428846d2a84d2ac164fd914))
+* **report:** `Report::new_boxed` ([0660d2f4](https://github.com/zkat/miette/commit/0660d2f43c0a793b1e289b26bcca73c8733bdcff))
+* **error:** `impl AsRef<dyn StdError> for Report` ([1a27033d](https://github.com/zkat/miette/commit/1a27033d7afd0007907550b1fc9d589d6f658662))
+
+### Bug Fixes
+
+* **wrapper:** complete forwarding `Diagnostic` implementations ([3fc5c04c](https://github.com/zkat/miette/commit/3fc5c04cbbd4b92863290a488a23d5243c16fe60))
+
+<a name="5.3.1"></a>
+## 5.3.1 (2022-09-10)
+
+### Bug Fixes
+
+* **miri:** Resolve Miri's concerns around unsafe code (#197) ([5f3429b0](https://github.com/zkat/miette/commit/5f3429b0626034328a0c2f1317b8a0e712c63775))
+* **graphical:** Align highlights correctly with wide unicode characters and tabs (#202) ([196c09ce](https://github.com/zkat/miette/commit/196c09ce7af9e54b63aaa5dae4cd199f2ecba3fa))
+
+<a name="5.3.0"></a>
+## 5.3.0 (2022-08-10)
+
+### Bug Fixes
+
+* **utils:** Fix off-by-one error in SourceOffset::from_location (#190) ([c3e6c983](https://github.com/zkat/miette/commit/c3e6c983363af7f7a88e52d50d57404defb1bf49))
+
+### Features
+
+* **graphical:** Allow miette users to opt-out of the rendering of the cause chain (#192) ([b9ea5871](https://github.com/zkat/miette/commit/b9ea587159464c0090d9510567e5ea93bb772b49))
+
+<a name="5.2.0"></a>
+## 5.2.0 (2022-07-31)
+
+### Features
+
+* **json:** `causes` support (#188) ([c95f58c8](https://github.com/zkat/miette/commit/c95f58c87a1335e956be23879754ac312a2b0853))
+
+### Bug Fixes
+
+* **docs:** readme was getting cut off during generation ([e286c705](https://github.com/zkat/miette/commit/e286c705fda28c02df67a584c0a013a1bbc38968))
+
+<a name="5.1.1"></a>
+## 5.1.1 (2022-07-09)
+
+### Bug Fixes
+
+* **deps:** bump minimum supports-color version (#182) ([ccf1b8ad](https://github.com/zkat/miette/commit/ccf1b8ade5b631e05fad79d1f9c5d268706d118e))
+* **graphical:** handle an empty source (#183) ([12dc4007](https://github.com/zkat/miette/commit/12dc40070a99ac91b67e23f7c15ce8151965fc81))
+
+<a name="5.1.0"></a>
+## 5.1.0 (2022-06-25)
+
+### Features
+
+* **protocol:** Implement SourceCode for Arc<str> (and similar types) (#181) ([85da6a84](https://github.com/zkat/miette/commit/85da6a8407ef727b8f77184b8a61f5b9a7d3ccef))
+
+<a name="5.0.0"></a>
+## 5.0.0 (2022-06-24)
+
+### Breaking Changes
+
+* **theme:** restructure automatic color selection (#177) ([1816b06a](https://github.com/zkat/miette/commit/1816b06a2efcd5705dfe91147ab5651fe0b517d6))
+    * The default theme now prefers ANSI colors, even if RGB is supported
+    * `MietteHandlerOpts::ansi_colors` is removed
+    * `MietteHandlerOpts::rgb_color` now takes an enum that controls the color
+      format used when color support is enabled, and has no effect otherwise.
+
+### Bug Fixes
+
+* **json:** Don't escape single-quotes, that's not valid json (#180) ([b193d3c0](https://github.com/zkat/miette/commit/b193d3c002be8a42fd199911cef3465e2e0cb593))
+
+<a name="4.7.1"></a>
+## 4.7.1 (2022-05-13)
+
+### Bug Fixes
+
+* **tests:** add Display impl to diagnostic_source example ([0a4cf4ad](https://github.com/zkat/miette/commit/0a4cf4ad24eb668d6668400b9ab3e8c896b33e3a))
+
+<a name="4.7.0"></a>
+## 4.7.0 (2022-05-05)
+
+### Features
+
+* **diagnostic_source:** add protocol method for Diagnostic-aware source chaining (#165) ([bc449c84](https://github.com/zkat/miette/commit/bc449c842662909d93d3a6b7e117fdbde77544e7))
+
+### Documentation
+
+* **IntoDiagnostic:** Warn of potential data loss (#161) ([2451ad6a](https://github.com/zkat/miette/commit/2451ad6a963c222831977e89542a7349b66f11cf))
+
+<a name="4.6.0"></a>
+## 4.6.0 (2022-04-23)
+
+### Features
+
+* **spans:** add From shorthand for zero-length SourceSpans ([1e1d6152](https://github.com/zkat/miette/commit/1e1d61525381a6699deba103a3829874676eee9c))
+* **related:** print related prefixes according to severity (#158) ([084ed138](https://github.com/zkat/miette/commit/084ed138b7598d549f38fe873a758d0ed03ef2b1))
+
+### Bug Fixes
+
+* **graphical:** fix issue with duplicate labels when span len is 0 (#159) ([1a36fa7e](https://github.com/zkat/miette/commit/1a36fa7ec80de77e910e04cdb902270970611b39))
+
+<a name="v4.5.0"></a>
+## 4.5.0 (2022-04-18)
+
+### Features
+
+* **spans:** make SourceSpan implement Copy (#151) ([5e54b29a](https://github.com/zkat/miette/commit/5e54b29acf87eacf0a0255a9d3db8966de697fcf))
+* **help:** update macro to allow optional help text (#152) ([45093c2f](https://github.com/zkat/miette/commit/45093c2f587a281a37e80141d126d87944ca75b5))
+* **labels:** allow optional labels in derive macro (#153) ([23ee3642](https://github.com/zkat/miette/commit/23ee3642d198ff4f78af9729d7a5223b0c676d1f))
+* **help:** allow non-option values in #[help] fields ([ea55f458](https://github.com/zkat/miette/commit/ea55f458fa8acabc1c7e001c405f90025d6dbafc))
+* **label:** use macro magic instead of optional flag for optional labels ([9da62cd0](https://github.com/zkat/miette/commit/9da62cd05d777f8bd962f1fe94a75c47b11ee07e))
+
+### Bug Fixes
+
+* **theme:** set correct field in MietteHandlerOpts::ansi_colors (#150) ([97197601](https://github.com/zkat/miette/commit/97197601ee8f36fedb559c9c8b2d73ce5b0ca0ee))
+
+<a name="v4.4.0"></a>
+## 4.4.0 (2022-04-04)
+
+### Features
+
+* **report:** Add conversion from Report to Box<dyn Error> (#149) ([b4a9d4cd](https://github.com/zkat/miette/commit/b4a9d4cd9bc43720613b7d2bb6b521d51922c6b8))
+
+### Bug Fixes
+
+* **docsrs:** use proper module names for docsrs URLs ([a0b972f8](https://github.com/zkat/miette/commit/a0b972f8765040fdbb08fdbe006ceb4dbc9c31f2))
+* **clippy:** misc clippy fixes ([b98b0982](https://github.com/zkat/miette/commit/b98b09828215ffc623aa17aa0bc8a6f45173a3f0))
+* **fmt:** cargo fmt ([37cda4a3](https://github.com/zkat/miette/commit/37cda4a3a456060050e42a199a68ab86ee679f79))
+
+<a name="v4.3.0"></a>
+## 4.3.0 (2022-03-27)
+
+### Features
+
+* **reporter:** Allow GraphicalReportHandler to disable url display (#137) ([b6a6cc9e](https://github.com/zkat/miette/commit/b6a6cc9e75198e53f1413c88694d950006833e05))
+
+### Bug Fixes
+
+* **colors:** handler_opts.color(false) should disable color (#133) ([209275d4](https://github.com/zkat/miette/commit/209275d4377fcaf397bde931f2972a1b7d8ce55c))
+* **handler:** Apply MietteHandlerOpts::graphical_theme (#138) ([70e84f9a](https://github.com/zkat/miette/commit/70e84f9a019008a38ed22416f1fc399d32f50db4))
+
+### Documentation
+
+* **readme:** Fix a couple links (#141) ([126ffc58](https://github.com/zkat/miette/commit/126ffc5834683726fc8efff6604735f8cc806f9b))
+
+### Miscellaneous Tasks
+
+* **deps:** Update textwrap to 0.15.0 (#143) ([2d0054b3](https://github.com/zkat/miette/commit/2d0054b3c9bf1f6bdbea624ba65593ca41f03999))
+
+<a name="v4.2.1"></a>
+## 4.2.1 (2022-02-25)
+
+### Bug Fixes
+
+* **handlers:** source code propagation for JSON handler (#122) ([50bcec90](https://github.com/zkat/miette/commit/50bcec909aa60c20d4981484195130fbb9f3cacb))
+* **clippy:** 1.59.0 clippy fix ([fa5b5fee](https://github.com/zkat/miette/commit/fa5b5fee549e53e9cf0c1d946bef242eebee6c48))
+* **docs:** Docs overhaul (#124) ([5d23c0d6](https://github.com/zkat/miette/commit/5d23c0d61d0c7e778579d4d290b1f6e2c53fba31))
+
+<a name="v4.2.0"></a>
+## 4.2.0 (2022-02-22)
+
+### Features
+
+* **derive:** allow `Report` in `related` (#121) ([75d4505e](https://github.com/zkat/miette/commit/75d4505e7d55e816cac071eb126213b72bf48982))
+
+<a name="v4.1.0"></a>
+## 4.1.0 (2022-02-20)
+
+`.with_source_code()` is here!!
+
+### Features
+
+* **report:** add `with_source_code` ([50519264](https://github.com/zkat/miette/commit/50519264d47d35ecbbe4846cf7d64139854adf6c))
+* **handlers:** propagate source code to related errors ([3a17fcea](https://github.com/zkat/miette/commit/3a17fceabb0641c3d44f73a62b8116cc87d3c6bb))
+
+### Bug Fixes
+
+* **derive:** absolute path references to Diagnostic (#118) ([6eb3d2d8](https://github.com/zkat/miette/commit/6eb3d2d8a63bc38a53a472932a476b78c4fdb34c))
+
+<a name="v4.0.1"></a>
+## 4.0.1 (2022-02-18)
+
+### Bug Fixes
+
+* **graphical:** boolean was messing up graphical display ([5c085b39](https://github.com/zkat/miette/commit/5c085b39e28ad87777135bcca30d2ac99039de39))
+
+<a name="v4.0.0"></a>
+## 4.0.0 (2022-02-18)
+
+### Breaking Changes
+
+* **colors:** treat no-color mode as no-color instead of narratable (#94) ([9dcce5f1](https://github.com/zkat/miette/commit/9dcce5f1bdd76e7564d604ab8b87bbc7caad310a))
+    * **BREAKING CHANGE**: NO_COLOR no longer triggers the narrated handler. Use
+NO_GRAPHICS instead.
+* **derive:** Make derive macro `diagnostic` attribute more flexible. (#115) ([5b8b5478](https://github.com/zkat/miette/commit/5b8b5478b63e91a51fadec87c6fed3e60d192b60))
+    * **BREAKING CHANGE**: `diagnostic` attribute duplication will now error.
+
+### Features
+
+* **Report:** adds `.context()` method to the `Report` (#109) ([2649fd27](https://github.com/zkat/miette/commit/2649fd27c47893dc3ba2445a9932600d1b3d3e63))
+
+### Bug Fixes
+
+* **handlers:** Fix label position (#107) ([f158f4e3](https://github.com/zkat/miette/commit/f158f4e370bd25d589136a69058a6dff5e8aa468))
+
+
+<a name="v3.3.0"></a>
+## 3.3.0 (2022-01-08)
+
+### Features
+
+* **deps:** Bump owo-colors to 3.0.0 ([fe77d8c7](https://github.com/zkat/miette/commit/fe77d8c75478e9915a61613ec94b3de0a70e5e26))
+* **handlers:** Add JSON handler (#90) ([53b24682](https://github.com/zkat/miette/commit/53b246829a2cf6317fe1ac0cf7603e37ffde349f))
+
+### Bug Fixes
+
+* **chain:** correct `Chain` structure exported (#102) ([52e5ec80](https://github.com/zkat/miette/commit/52e5ec806457c2784d85dc4e4a332c07e6eea818))
+* **json:** proper escapes for JSON strings (#101) ([645ef6a1](https://github.com/zkat/miette/commit/645ef6a1b66a9a05f97883535f162cab4d0483f5))
+* **deps:** switch to terminal_size ([51146535](https://github.com/zkat/miette/commit/51146535f5ea9eeaff1163d99d8b89a2567e93dd))
+
+<a name="v3.2.0"></a>
+## 3.2.0 (2021-10-06)
+
+### Features
+
+* **tabs:** Add replace tabs with spaces option (#82) ([1f70140c](https://github.com/zkat/miette/commit/1f70140c2e6a57237de78dab022e29440f98ae33))
+
+### Bug Fixes
+
+* **read_span** prevent multiline MietteSpanContents from skipping lines (#81) ([cb5a919d](https://github.com/zkat/miette/commit/cb5a919deb87f8fba748bed73b6f22ebe4e3390f))
+
+<a name="v3.1.0"></a>
+## 3.1.0 (2021-10-01)
+
+### Features
+
+* **SourceSpan:** add impl From<Range> (#78) ([0169fe20](https://github.com/zkat/miette/commit/0169fe20e7868cfee594b26b063267d17be0a84e))
+
+<a name="v3.0.1"></a>
+## 3.0.1 (2021-09-26)
+
+No code changes this release. Just improved documentation and related tests.
+
+<a name="v3.0.0"></a>
+## 3.0.0 (2021-09-22)
+
+It's here! Have fun!
+
+It's a pretty significant change, so if you were using `miette`'s snippet
+support previously, you'll need to update your code.
+
+### Bug Fixes
+
+* **report:** miscellaneous, hacky tweaks to graphical rendering ([80036781](https://github.com/zkat/miette/commit/80036781cda11de071187d59127c6d1c7cafa879))
+* **protocol:** implement source/cause for Box<dyn Diagnostic> ([c3505fac](https://github.com/zkat/miette/commit/c3505fac269aebadc0fd62f9ee4e04bd00970dae))
+* **derive:** Code is no longer required ([92a31509](https://github.com/zkat/miette/commit/92a3150921d366e2850249be14259a550fcee3bb))
+* **graphical:** stop rendering red vbars before the last item ([e2e4027f](https://github.com/zkat/miette/commit/e2e4027fda55415ac07590e2d33e1f6d762df439))
+* **graphical:** fix coalescing adjacent things when they cross boundaries ([18e0ed77](https://github.com/zkat/miette/commit/18e0ed7749d33c5030a5fa2f8eabdc50a717573b))
+* **context:** get labels/snippets working when using .context() ([41cb710a](https://github.com/zkat/miette/commit/41cb710a7dff59a9bde126556be7f5a877c1dafd))
+* **api:** put panic handler properly behind a flag ([55ca8e0b](https://github.com/zkat/miette/commit/55ca8e0b7ff60cef8a7f75c29fa78edbb8114043))
+* **deps:** We do not use ci_info directly anymore ([8d1170e2](https://github.com/zkat/miette/commit/8d1170e2decee290f1679b823eb0f7ea04f3fb39))
+* **graphical:** Fix off-by-one span_applies calculation (#70) ([a6902042](https://github.com/zkat/miette/commit/a69020422e546efbe9256e30d9da10ad67f5ce03))
+* **theme:** remove code styling ([ce0dea54](https://github.com/zkat/miette/commit/ce0dea541a60f274bd97d3a1cfdaa9d217b632e2))
+* **graphical:** render URLs even without a code ([77c5899b](https://github.com/zkat/miette/commit/77c5899bbd7c46733ea208a7506c1d07b773bc2c))
+* **deps:** remove dep on itertools ([612967d3](https://github.com/zkat/miette/commit/612967d381f05e2e5a27e39a7a66942c7ec396f3))
+
+### Features
+
+* **report:** make a single big MietteHandler that can switch modes ([4c2463f9](https://github.com/zkat/miette/commit/4c2463f9aeaef43f69cac3abae059973f430bfa8))
+    * **BREAKING CHANGE**: linkification option method on GraphicalReportHandler has been changed to .with_links(bool)
+* **deps:** move fancy reporter (and its deps) to a feature ([247e8f8b](https://github.com/zkat/miette/commit/247e8f8b39271ffa7fd2c461e8ed769bebcbc589))
+    * **BREAKING CHANGE**: The default fancy reporter is no longer available unless you enable the "fancy" feature. This also means you will not be pulling in a bunch of deps if you are using miette for a library
+* **footer:** add footer support to graphical and narrated ([93374173](https://github.com/zkat/miette/commit/93374173e30c5d4ccdd0aa16557d68d54aaf3e59))
+* **theme:** rename some theme items for clarity ([c5c0576e](https://github.com/zkat/miette/commit/c5c0576ec69d5ccc3700dd6fc411d071bb0114a7))
+    * **BREAKING CHANGE**: These were part of the public API, so if you were using theming, this might have broken for you
+* **theme:** more styling changes ([2c437403](https://github.com/zkat/miette/commit/2c43740346da954fd71653a079c53a1e9612c06f))
+* **report:** add debug report as default, instead of narrated one ([9841d6fd](https://github.com/zkat/miette/commit/9841d6fd77ce665acb40f7459f410e83cdc131c0))
+* **labels:** replace snippet stuff with simpler labels (#62) ([f87b158b](https://github.com/zkat/miette/commit/f87b158b22f6f943cd7e52ca186b5f3c542194fd))
+* **protocol:** Make SourceCode Send+Sync ([9aa8ff0d](https://github.com/zkat/miette/commit/9aa8ff0d3190e0fb1ee5ad48cb540b961fc46366))
+* **handlers:** Update graphical handler to use new label protocol (#66) ([4bb9d121](https://github.com/zkat/miette/commit/4bb9d12102c1e24b6f063e43bd87e894f16683e8))
+* **report:** nicer, non-overlapping same-line highlights ([1a0f359e](https://github.com/zkat/miette/commit/1a0f359e3cd386f2738052d68790a3b54e64055b))
+* **panic:** Add basic panic handler and installation function ([c6daee7b](https://github.com/zkat/miette/commit/c6daee7b930ff7b76ce6ab394460c7659124f2d6))
+* **panic:** add backtrace support to panic handler and move set_panic_hook into fancy features ([858ac169](https://github.com/zkat/miette/commit/858ac169353e653ed0795fb1962f4ddde8fc3d06))
+* **graphical:** simplify graphical header and remove a dep ([6c648463](https://github.com/zkat/miette/commit/6c6484633ed1580047fb3dc820486f3264fb6a19))
+* **related:** Add related diagnostics (#68) ([8e11baab](https://github.com/zkat/miette/commit/8e11baab7b7b57d6220cf31a82715ac9b8b76f2f))
+* **graphical:** compact graphical display a bit ([db637a36](https://github.com/zkat/miette/commit/db637a366b1bcf54ff761a43ddb2cdfaaac0e481))
+* **graphical:** compact even more ([72c0bb9e](https://github.com/zkat/miette/commit/72c0bb9e65fa2fc7e8a1cf61ab1fe636ec063d2e))
+* **graphical:** add theming customization for linums ([717f8e3d](https://github.com/zkat/miette/commit/717f8e3d8837e14d76825603c0cbdcabb66950ff))
+* **handler:** context lines config support ([b33084bd](https://github.com/zkat/miette/commit/b33084bdbfeec90208f9dacd1976c8bde31642f3))
+* **narrated:** updated narrated handler ([fbf6664e](https://github.com/zkat/miette/commit/fbf6664ef5582c9a15bba881a6ee1ca058102d7f))
+* **narrated:** global footer and related diagnostics support ([3213fa61](https://github.com/zkat/miette/commit/3213fa610a17e3f52ece8c069eb123b2a38f1266))
+
+<a name="3.0.0-beta.0"></a>
+## 3.0.0-beta.0 (2021-09-22)
+
+Time to get ready for release!
+
+### Bug Fixes
+
+* **graphical:** stop rendering red vbars before the last item ([dc2635e1](https://github.com/zkat/miette/commit/dc2635e15154ab33506bdeae46f34c99b403fff2))
+* **graphical:** fix coalescing adjacent things when they cross boundaries ([491ce7c0](https://github.com/zkat/miette/commit/491ce7c0ce1f04c9b6fc09c250f188c1ec77df53))
+* **context:** get labels/snippets working when using .context() ([e0296578](https://github.com/zkat/miette/commit/e02965787b5e6206dad46556a50edae578449789))
+
+### Features
+
+* **report:** nicer, non-overlapping same-line highlights ([338c885a](https://github.com/zkat/miette/commit/338c885a305035fc21f63e3566131af5befa14b3))
+* **panic:** Add basic panic handler and installation function ([11a708a2](https://github.com/zkat/miette/commit/11a708a2244f1838351b2b59bfc407febe3c2a0e))
+* **panic:** add backtrace support to panic handler and move set_panic_hook into fancy features ([183ecb9b](https://github.com/zkat/miette/commit/183ecb9b78a1c22d832e979db5054dcac36d8b7a))
+* **graphical:** simplify graphical header and remove a dep ([9f36a4c2](https://github.com/zkat/miette/commit/9f36a4c25362486dfcf9ad2bd66c45e47d6fa4d2))
+* **related:** Add related diagnostics (#68) ([25e434a2](https://github.com/zkat/miette/commit/25e434a2cec93e41f020372dedcf395adb2564de))
+* **graphical:** compact graphical display a bit ([9d07dc5a](https://github.com/zkat/miette/commit/9d07dc5a1c190b6d52770e4f3c4a1dabd53e0fd5))
+* **graphical:** compact even more ([712e75fd](https://github.com/zkat/miette/commit/712e75fd8c25c6309a49c7f81f83d5b6f855594c))
+
+<a name="3.0.0-alpha.0"></a>
+## 3.0.0-alpha.0 (2021-09-20)
+
+This is the first WIP alpha release of miette 3.0!
+
+It's a MAJOR rewrite of the entire snippet definition and rendering system,
+and you can expect even more changes before 3.0 goes live.
+
+In the meantime, there's this. :)
+
+### Bug Fixes
+
+* **report:** miscellaneous, hacky tweaks to graphical rendering ([8029f9c6](https://github.com/zkat/miette/commit/8029f9c6c39d9d9592a2183380e83add8f9938e1))
+* **protocol:** implement source/cause for Box<dyn Diagnostic> ([3e8a27e2](https://github.com/zkat/miette/commit/3e8a27e263d6b22c1f2a9b192b2d305c2f0aa367))
+* **derive:** Code is no longer required ([8a0f71e6](https://github.com/zkat/miette/commit/8a0f71e6d11cd6f89fbad67cce46e34aa75f3b39))
+
+### Features
+
+* **report:** make a single big MietteHandler that can switch modes ([3d74a500](https://github.com/zkat/miette/commit/3d74a500c3193fb1dff26591191a67eaab079671))
+    * **BREAKING CHANGE**: linkification option method on GraphicalReportHandler has been changed to .with_links(bool)
+* **deps:** move fancy reporter (and its deps) to a feature ([bc495e6e](https://github.com/zkat/miette/commit/bc495e6ed49f227895260d8877685e267c0d5814))
+    * **BREAKING CHANGE**: The default fancy reporter is no longer available unless you enable the "fancy" feature. This also means you will not be pulling in a bunch of deps if you are using miette for a library
+* **footer:** add footer support to graphical and narrated ([412436cd](https://github.com/zkat/miette/commit/412436cd689ac55e9ec8172f772c321288629553))
+* **theme:** rename some theme items for clarity ([12a9235b](https://github.com/zkat/miette/commit/12a9235bec53d6dbd347f43dfaef167696a381e1))
+    * **BREAKING CHANGE**: These were part of the public API, so if you were using theming, this might have broken for you
+* **theme:** more styling changes ([9901030e](https://github.com/zkat/miette/commit/9901030eb160e72bc64144c44b8bf48cce8dfe48))
+* **report:** add debug report as default, instead of narrated one ([eb1b7222](https://github.com/zkat/miette/commit/eb1b7222fc5b73b6fb8fee90b1de27e0b8d6d588))
+* **labels:** replace snippet stuff with simpler labels (#62) ([0ef2853f](https://github.com/zkat/miette/commit/0ef2853f27ea84407789cbd0680956f9e3ee9168))
+* **protocol:** Make SourceCode Send+Sync ([eb485658](https://github.com/zkat/miette/commit/eb485658cc5a0df894c59d6ad29f945fff2839a5))
+* **handlers:** Update graphical handler to use new label protocol (#66) ([6cd44a86](https://github.com/zkat/miette/commit/6cd44a86c6e6f1d9c79006d4cfa89220dbd3a7b4))
+
+
+<a name="2.2.0"></a>
+## 2.2.0 (2021-09-14)
+
+So it turns out [`3.0.0` is already under way](https://github.com/zkat/miette/issues/45), if you didn't already hear!
+
+It's going to be an exciting release, but we'll still be putting out bugfixes
+and (backwards-compatible) features in the `2.x` line until that's ready.
+
+And there's definitely stuff in this one to be excited about! Not least of all
+the ability to _forward_ diagnostic metadata when wrapping other
+`Diagnostic`s. Huge thanks to [@cormacrelf](https://github.com/cormacrelf) for
+that one!
+
+We've also got some nice improvements to reporter formatting that should make
+output look at least a little nicer--most notably, we now wrap messages and
+footers along the appropriate column so formatting keeps looking good even
+when you use newlines!
+
+Finally, huge thanks to [@icewind1991](https://github.com/icewind1991) for
+fixing a [really weird-looking bug](https://github.com/zkat/miette/pull/52)
+caused by an off-by-one error. Oopsies 😅
+
+### Features
+
+* **report:** wrap multiline messages to keep formatting ([f482dcec](https://github.com/zkat/miette/commit/f482dcec6a4e981c256854f73506ed01abaa65f9))
+* **report:** take terminal width into account for wrapping text ([bc725324](https://github.com/zkat/miette/commit/bc72532465bde00e11d83ff4a9f767051ee6771d))
+* **report:** make header line as wide as terminal ([eaebde92](https://github.com/zkat/miette/commit/eaebde92cf528d50d799dd60acd98b16978e8681))
+* **derive:** Add `#[diagnostic(forward(field_name), code(...))]` (#41) ([2fa5551c](https://github.com/zkat/miette/commit/2fa5551c81831734fd9a162463a4a939dff9dfba))
+
+### Bug Fixes
+
+* **report:** get rid of the weird arrow thing. it does not look good ([1ba3f2f5](https://github.com/zkat/miette/commit/1ba3f2f5d292419571302477195836f89d9c7cb5))
+* **report:** fix wrapping for header and add wrapping for footer ([eb07d5bd](https://github.com/zkat/miette/commit/eb07d5bd66928457b4f3affe96aa6a0d39f642f7))
+* **report:** Fix end of previous line wrongly being included in highlight (#52) ([d994add9](https://github.com/zkat/miette/commit/d994add912700873de3ebdb8d14d81516955c901))
+
+<a name="2.1.2"></a>
+## 2.1.2 (2021-09-10)
+
+So it turns out I forgot to make snippets and other stuff forward through when
+you use `.context()` &co. This should be fixed now 😅
+
+### Bug Fixes
+
+* **context:** pass on diagnostic metadata when wrapping with `Report` ([e4fdac38](https://github.com/zkat/miette/commit/e4fdac38ea8c295468ed0fce563a2df29241986a))
+
+<a name="2.1.1"></a>
+## 2.1.1 (2021-09-09)
+
+This is a small, but visually-noticeable bug fix. I spent some time playing
+with colors and styling and made some fixes that will improve where people's
+eyes are drawn to, and also take into account color visibility issues a bit
+more.
+
+### Bug Fixes
+
+* **report:** don't color error message text to draw eyes back to it ([6422f821](https://github.com/zkat/miette/commit/6422f8217495aeef38af4eb00feeb73ced36f7bf))
+* **reporter:** improve color situation and style things a little nicer ([533ff5f3](https://github.com/zkat/miette/commit/533ff5f348324132044bd2782a17fd6c81c08259))
+
+<a name="2.1.0"></a>
+## 2.1.0 (2021-09-08)
+
+This is a small release with a handful of quality of life improvements (and a small bugfix).
+
+### Features
+
+* **printer:** use uparrow for empty highlights and fix 0-offset display bug ([824cd8be](https://github.com/zkat/miette/commit/824cd8bebea2ae43a29d9d744d0386d00cc943e0))
+* **derive:** make #[diagnostic] optional for enums, too ([ffe1b558](https://github.com/zkat/miette/commit/ffe1b558d0d7284e39fcb38c4f410cddb4cdb4bd))
+
+<a name="2.0.0"></a>
+## 2.0.0 (2021-09-05)
+
+This release overhauls the toplevel/main experience for `miette`. It adds a
+new `Report` type based on `eyre::Report` and overhauls various types to fit
+into this model, as well as prepare for some [future changes in
+Rust](https://github.com/nrc/rfcs/pull/1) that will make it possible to
+integrate `miette` directly with crates like `eyre` instead of having to use
+this specific `Report`.
+
+On top of that, it includes a couple of nice new features, such as
+`#[diagnostic(transparent)]`, which should be super useful when wrapping other
+diagnostics with your own types!
+
+### Breaking Changes
+
+* **report:** anyhow-ify DiagnosticReport (#35) ([3f9da04b](https://github.com/zkat/miette/commit/3f9da04b866f3fd90f88e7e60f9fb7a322aef568))
+    * `DiagnosticReport` is now just `Report`, and is a different, `eyre::Report`-like type.
+    * `DiagnosticResult` is now just `Result`.
+    * `.into_diagnostic()` now just transforms the error into a `Report`.
+    * `DiagnosticReportPrinter` has been replaced with `ReportHandler`
+    * `set_printer` has been replaced by `set_hook`
+    * `code` is now optional.
+    * `.into_diagnostic()` no longer takes a `code` argument.
+    * `#[diagnostic]` is now optional when deriving `Diagnostic`.
+
+### Features
+
+* **derive:** Add `#[diagnostic(transparent,forward)]` (#36) ([53f5d6d1](https://github.com/zkat/miette/commit/53f5d6d1d62845b52e590fed5ce91a643b6e11f3))
+* **Source:** impl Source for str, &str (make &'static str usable for testing) (#40) ([50c7a883](https://github.com/zkat/miette/commit/50c7a88360dc7cef815af2dbb9dc18ede0d1fdb4))
+* **source:** Remove bound `T: Clone` from `Source` implementation for `Cow`. (#42) ([0427c9f9](https://github.com/zkat/miette/commit/0427c9f9666222084cb4494aabbd3e7dc5cdb789))
+
+### Bug Fixes
+
+* **reporter:** Only inc the line count if we haven't already done so with '\n' or '\r\n' (#37) ([5a474370](https://github.com/zkat/miette/commit/5a474370ddda92a3a92b6b84cd561ecaf4d6d858))
+* **printer:** Show snippet message for unnamed sources (#39) ([84219f6c](https://github.com/zkat/miette/commit/84219f6c80c2c432fbeb4c40a591380285de8767))
+
+<a name="1.1.0"></a>
+## 1.1.0 (2021-08-29)
+
+This is a small release of patches entirely not my own!
+
+The exciting new feature is the ability to do `thiserror`-style
+`#[diagnostic(transparent)]` when using the derive macro, which will defer
+diagnostics to a Diagnostic referred to by the struct/enum!
+
+Big thanks to [@cormacrelf](https://github.com/cormacrelf) and
+[@felipesere](https://github.com/felipesere) for your contributions!
+
+### Features
+
+* **derive:** Add `#[diagnostic(transparent,forward)]` (#36) ([53f5d6d1](https://github.com/zkat/miette/commit/53f5d6d1d62845b52e590fed5ce91a643b6e11f3))
+
+### Bug Fixes
+
+* **reporter:** Only inc the line count if we haven't already done so with '\n' or '\r\n' (#37) ([5a474370](https://github.com/zkat/miette/commit/5a474370ddda92a3a92b6b84cd561ecaf4d6d858))
+
+<a name="1.0.1"></a>
+## 1.0.1 (2021-08-23)
+
+This is a (literally) small release. I noticed that the crate's size had
+increased significantly before I realized cargo was including the `images/`
+folder. This is not needed, as these images are just hosted on GitHub.
+
+`miette` should be smaller now, I hope :)
+
+#### Bug Fixes
+
+* **crate:**  reduce crate size by removing images ([5f74da67](https://github.com/zkat/miette/commit/5f74da671f2444efc4840c11492773a46cecf7e9))
+
+
+<a name="1.0.0"></a>
+## 1.0.0 (2021-08-23)
+
+...you know what? I'm just gonna tag 1.0.0, because I don't want sub-1.0
+versions anymore, but the Cargo ecosystem buries pre-releases pretty
+thoroughly. Integers are cheap!
+
+So here we are! We made it to 1.0, and with some _really_ nice goodies to boot.
+
+Most fun is the fact that the default printer now has *clickabble url linking*
+support. A new `Diagnostic::url()` method has been added to the protocol that,
+is used to figure out what URL to send folks to! This should work on most
+"modern" terminals, but more thorough support checking will be done in the
+future. And of course, the narrated reporter prints them out too.
+
+I also took the time to completely redo how messages, labels, and filenames
+are handled in the system, and this is a pretty big change you might run into.
+Godspeed!
+
+Last but not least, we got our first external contribution! Thank you to
+[@martica](https://github.com/martica) for the bug fix!
+
+Anyway, here's to 1.0, and to many more after that. Enjoy! :)
+
+#### Breaking Changes
+
+* **snippets:**  Overhauled how snippets handle labels, sources, and messages, including the derive macro ([61283e9e](https://github.com/zkat/miette/commit/61283e9efe2825425c41027b3dbb5f4f9c9d83fb)
+
+#### Features
+
+* **links:**  added URL linking support and automatic docs.rs link generation ([7e76e2de](https://github.com/zkat/miette/commit/7e76e2dea4adf0e4a1349e049495c1f5a0bdab87))
+* **theme:**  Add an initial `rgb` style with nicer colors ([3546dcec](https://github.com/zkat/miette/commit/3546dcec988ea40cc6aa8dd94c29432830cef662)) - [@martica](https://github.com/martica)
+
+#### Bug Fixes
+
+* **printer:**  clamp highlight length to at least 1 (#32) ([9d601599](https://github.com/zkat/miette/commit/9d6015996bf3010b573b9bb5d0e48cb85f290460))
+
+
+<a name="1.0.0-beta.1"></a>
+## 1.0.0-beta.1 (2021-08-22)
+
+It's happening, folks! `miette` is now working towards stability and is now in
+beta! We'll keep it like this for a little while until a few more people have
+tried it out and given feedback. New features may still be added, and breaking
+changes may still happen, but `miette` is now considered "good enough to use",
+and breaking changes are expected to be more rare.
+
+Oh, and as part of this release, the docs were overhauled, particularly the
+README, so you might want to take a gander at them!
+
+#### Breaking Changes
+
+* **printer:**  rename default printer and consistify some naming conventions with printing ([aafa4a3d](https://github.com/zkat/miette/commit/aafa4a3de1298dd8e7625138d09a408ff3579d3f), breaks [#](https://github.com/zkat/miette/issues/))
+* **into_diagnostic:**  .into_diagnostic() is now generic across any impl fmt::Display instead of expecting a `dyn` ([c1da4a0d](https://github.com/zkat/miette/commit/c1da4a0d2744e94e409cabeafe911e99598d4ee3))
+
+#### Features
+
+* **error:**  diagnostic-ify MietteError ([e980b723](https://github.com/zkat/miette/commit/e980b7237334b56f7b8c092956d35cd2bbadac41))
+
+#### Bug Fixes
+
+* **derive:**  #[diagnosic(severity)] works for named and unnamed variants/structs now ([adf0bc93](https://github.com/zkat/miette/commit/adf0bc933f62852514067ade96e07362c889f012))
+* **protocol:**  oops, missed a spot after a rename ([5c077d30](https://github.com/zkat/miette/commit/5c077d30a4aca71f71e61b2561081575c04a4d64))
+
+
+<a name="0.13.0"></a>
+## 0.13.0 (2021-08-21)
+
+This release includes some accessibility improvements: miette now includes a "narratable" printer that formats diagnostics like this:
+
+```
+Error: Received some bad JSON from the source. Unable to parse.
+    Caused by: missing field `foo` at line 1 column 1700
+
+Begin snippet for https://api.nuget.org/v3/registration5-gz-semver2/json.net/index.json starting
+at line 1, column 1659
+
+snippet line 1: gs":["json"],"title":"","version":"1.0.0"},"packageContent":"https://api.nuget.o
+    highlight starting at line 1, column 1699: last parsing location
+
+diagnostic help: This is a bug. It might be in ruget, or it might be in the source you're using,
+but it's definitely a bug and should be reported.
+diagnostic error code: ruget::api::bad_json
+```
+
+This style is the default in a number of situations:
+
+1. The `NO_COLOR` env var is present and set, and not `0`.
+2. The `CLICOLOR` env var is present and not set to `1`.
+3. `stdout` or `stderr` are not TTYs.
+4. A CI environment is detected.
+
+You can override and customize this behavior any way you want by using the
+`miette::set_reporter()` function at the toplevel of your application, but we
+encourage you to at least make the narratable printer an option for your
+users, since miette's default printer is exceptionally bad for screen
+readers.
+
+Our hope is that this release is only the starting point towards making
+miette's error reporting not just really fancy and cool, but friendly and
+accessible to everyone.
+
+#### Features
+
+* **printer:**  added (and hooked up) an accessible report printer ([5369a942](https://github.com/zkat/miette/commit/5369a9424e7ed2c66b193b85422fe8b98bc37b6c))
+
+
+<a name="0.12.0"></a>
+## 0.12.0 (2021-08-21)
+
+This is a SUPER EXCITING release! With this, miette now has a full-featured
+pretty-printer that can handle cause chains, snippets, help text, and lots
+more!
+
+Check out [the serde_json
+example](https://github.com/zkat/miette/blob/5fd2765bf05edf25251ce199994b8815524fd47d/images/serde_json.png)
+to see a "real-world" case!
+
+This release also adds support for full `thiserror`-style format strings to
+the `help()` diagnostic derive attribute!
+
+We're rapidly approaching a 1.0-beta release. One more extra-fun treat left
+and we can start stabilizing!
+
+#### Features
+
+* **derive:**  format string support for help() ([8fbad1b1](https://github.com/zkat/miette/commit/8fbad1b1cd173ce3c0b803f8b2db013e278c63a6))
+* **printer:**  lots of small improvements to printer ([5fbcd530](https://github.com/zkat/miette/commit/5fbcd53026c131ceafe2a66bebbc20de570363c9))
+* **reporter:**  fancy new reporter with unicode, colors, and multiline (#23) ([d675334e](https://github.com/zkat/miette/commit/d675334e48ddc188a34e166ad040eaceda117d0a))
+
+
+<a name="0.11.0"></a>
+## 0.11.0 (2021-08-18)
+
+BIG changes this time. The whole end-to-end experience for tossing around
+Diagnostics in your code has been overhauled, printing reports is easier than
+ever, and we even have an `eyre::Report`-style wrapper you can pass around in
+app-internal returns!
+
+#### Features
+
+* **reporter:**  Overhauled return type/main/DiagnosticReport experience. ([29c1403e](https://github.com/zkat/miette/commit/29c1403efdd7fd218f240ac458fd19bba17e9551))
+
+
+<a name="0.10.0"></a>
+## 0.10.0 (2021-08-17)
+
+Lots of goodies in this release! I'm working hard on the [1.0.0
+Roadmap](https://github.com/zkat/miette/issues/10), so things are changing
+pretty quick, and I thought it would be nice to release this checkpoint.
+#### Bug Fixes
+
+* **protocol:**  keep the owned spans ([49151bb0](https://github.com/zkat/miette/commit/49151bb0950c0db9d2743c8fb78dcacfc27bc750))
+
+#### Features/Breaking Changes
+
+* **derive:**  Allow anything Clone + Into<SourceSpan> to be used as a Span ([385171eb](https://github.com/zkat/miette/commit/385171eb8178ce2e7d6d2d2849b78e0f09feb721))
+* **offsets:**
+  *  nice utility function to get an offset from a Rust callsite ([26f409c5](https://github.com/zkat/miette/commit/26f409c5252c3fda5ead140eb4d5ec282f47f0f7))
+  *  utility function for converting from line/col to offset ([75c23127](https://github.com/zkat/miette/commit/75c2312755bf714c112badf6310b2bff1633f6bc))
+  *  more utility From impls for SourceSpan ([95200366](https://github.com/zkat/miette/commit/95200366a1639b0b729db460ae1e50cce6fee9de))
+* **protocol:**
+  *  add Source impls for Cow and Arc ([53074d34](https://github.com/zkat/miette/commit/53074d3488e1404331fc1ca3c5e068ac57e9a852))
+  *  reference-based DiagnosticReport! ([f390520b](https://github.com/zkat/miette/commit/f390520b45823d65055f9f872016e4ee27c0c20a))
+
+
+
+<a name="0.9.0"></a>
+## 0.9.0 (2021-08-17)
+
+Yay new version already! A pretty significant API change, too! ��
+
+#### Breaking Changes
+
+`SourceSpan`s have changed a bit: for one, they're based on offset/length now,
+instead of start/end. For two, they have a new `Option<String>` field,
+`label`, which is meant to be used by reporters in different contexts. For
+example, highlight snippets will use them as the labels for underlined
+sections of code, while the snippet context will use the label as the "file
+name" for the Source they point to.
+
+  * **protocol:** new SourceSpans with labels ([acfeb9c5](https://github.com/zkat/miette/commit/acfeb9c5b0e390c924194ee0363fc49fa8defbac))
+
+#### Bug Fixes
+
+* **derive:**  allow unused variables for the snippets method ([f704d6a9](https://github.com/zkat/miette/commit/f704d6a9ae971dfe61fe9a0e0b4a1a7f98fd37bc))
+
+#### Features
+
+* **protocol:** implement From<(usize, usize)> for SourceSpan ([36b86df9](https://github.com/zkat/miette/commit/36b86df9f51984405efa6f38be8bbb984d605207))
+
+
+
+<a name="0.8.1"></a>
+## 0.8.1 (2021-08-17)
+
+Just a small bump to update the readme (and docs.rs in the process) with the
+new snippet derive stuff. No notable changes.
+
+<a name="0.8.0"></a>
+## 0.8.0 (2021-08-17)
+
+You can full-on use `#[derive(Diagnostic)]` to define snippets now. That's a
+big deal.
+
+#### Features
+
+* **derive:**  Support for deriving snippet method (#18) ([f6e6acf2](https://github.com/zkat/miette/commit/f6e6acf2d2c301fd411c7c9c4b63a2b19aa69242))
+
+<a name="0.7.0"></a>
+## 0.7.0 (2021-08-16)
+
+Welp. `0.6.0` was basically completely broken, so I tore out the
+`darling`-based derive macros and rewrote the whole thing using `syn`, and
+things are much better now!
+
+There's still a few bits and bobs to add, like snippets (oof. big.), and full
+help format string support (they don't quite work in enums right now), but
+otherwise, this is pretty usable~
+
+#### Features
+
+* **derive:**  improved derive support, including partial help format string support! ([9ef0dd26](https://github.com/zkat/miette/commit/9ef0dd261fa537b280f32ea6f149785a69e33938))
+
+#### Bug Fixes
+
+* **derive:**  move to plain syn to fix darling issues ([9a78a943](https://github.com/zkat/miette/commit/9a78a943950078c879a1eb06baf819348139e1de))
+
+
+<a name="0.6.0"></a>
+## 0.6.0 (2021-08-15)
+
+We haz a basic derive macro now!
+
+#### Features
+
+* **derive:**  added basic derive macro ([0e770270](https://github.com/zkat/miette/commit/0e7702700de8a4cd9022d660aaf363b735943d55))
+
+
+<a name="0.5.0"></a>
+## 0.5.0 (2021-08-14)
+
+I decided to yank some handy (optional) utilities from a project I'm using
+`miette` in. These should make using it more ergonomic.
+
+#### Features
+
+* **utils:**  various convenience utilities for creating and working with Diagnostics ([a9601368](https://github.com/zkat/miette/commit/a960136802834bd3741ef637d91f73287870b1ad))
+
+
+<a name="0.4.0"></a>
+## 0.4.0 (2021-08-11)
+
+Time for another (still experimental!) change to `Diagnostic`. It will
+probably continue to change as miette gets experimented with, until 1.0.0
+stabilizes it. But for now, expect semi-regular breaking changes of this kind.
+
+Oh and I tracked down a rogue `\n` that was messing with the default reporter
+and managed to get out of it with at least some of my sanity.
+
+#### Breaking Changes
+
+* **protocol:**  Simplify protocol return values further ([02dd1f84](https://github.com/zkat/miette/commit/02dd1f84d45c01fb4de2d31c158a7b6e08455f72), breaks [#](https://github.com/zkat/miette/issues/))
+
+#### Bug Fixes
+
+* **reporter:**
+  *  fix reporter and tests... again ([d201dde4](https://github.com/zkat/miette/commit/d201dde4b559a2baa4259a0845582a5d14453c5a))
+  *  fix extra newline after header ([0d2e3312](https://github.com/zkat/miette/commit/0d2e3312a4a262e99a131bc893097d295e59e8ca))
+
+
+<a name="0.3.1"></a>
+## 0.3.1 (2021-08-11)
+
+This is a tiny release to fix a reporter rendering bug.
+
+#### Bug Fixes
+
+* **reporter:**  fix missing newline before help text ([9d430b6f](https://github.com/zkat/miette/commit/9d430b6f477fd8991ce217dffdbce8fbd28dcd7e))
+
+
+
+<a name="0.3.0"></a>
+## 0.3.0 (2021-08-08)
+
+This version is the result of a lot of experimentation with getting the
+`Diagnostic` API right, particularly `Diagnostic::snippets()`, which is
+something that should be writable in several different ways. As such, it
+includes some breaking changes, but they shouldn't be too hard to figure out.
+
+#### Breaking Changes
+
+* **protocol:**
+  *  improvements to snippets API ([3584dc60](https://github.com/zkat/miette/commit/3584dc600c2b8b0f84a2a0c59856da9a9dc7fbab))
+  *  help is a single Display ref now. ([80e7dabb](https://github.com/zkat/miette/commit/80e7dabbe450d4a78ed18174e2a383a6a1ed0557))
+
+#### Bug Fixes
+
+* **tests:**  updating tests ([60bdf47e](https://github.com/zkat/miette/commit/60bdf47e297999b48345b39ba1a3aacbbf79e6fc))
+
+<a name="0.2.1"></a>
+## 0.2.1 (2021-08-05)
+
+I think this is the right thing to do re: From!
+
+#### Bug Fixes
+
+* **protocol:**  fix the default From<:T Diagnostic> implementation to cover more cases. ([781a51f0](https://github.com/zkat/miette/commit/781a51f03765c7351a95b34e8391f6a0cf5fc37c))
+
+<a name="0.2.0"></a>
+## 0.2.0 (2021-08-05)
+
+Starting to get some good feedback on the protocol and APIs, so some improvements were made.
+
+#### Breaking changes
+
+You might need to add `+ Send + Sync + 'static` to your `Box<dyn Diagnostic>`
+usages now, since `Diagnostic` no longer constrains on any of them.
+
+Additionally, `Diagnostic::help()`, `Diagnostic::code()`, and `SpanContents`
+have had signature changes that you'll need to adapt to.
+
+* **protocol:**  protocol improvements after getting feedback ([e955321c](https://github.com/zkat/miette/commit/e955321cbd67372dfebb71a829ddb89baf9b169a))
+* **protocol:**  Make use of ? and return types with Diagnostics more ergonomic ([50238d75](https://github.com/zkat/miette/commit/50238d75a2db2dccbe2ae2cba78d0dd6eac4ef2a))
+
+<a name="0.1.0"></a>
+## 0.1.0 (2021-08-05)
+
+I'm really excited to put out this first release of `miette`! This version
+defines the current protocol and includes a basic snippet reporter. It's fully
+documented and ready to be used!
+
+_Disclaimer_: This library is still under pretty heavy development, and you should only use this if you're interested in using something experimental. Any and all design comments and ideas are welcome over on [GitHub](https://github.com/zkat/miettee)
+
+#### Bug Fixes
+
+* **api:**  stop re-exporting random things wtf??? ([2fb9f93c](https://github.com/zkat/miette/commit/2fb9f93cbf02c4d41a5538e98c8bea72f40c5430))
+* **protocol:**  use references for all return values in Diagnostic ([c3f41b97](https://github.com/zkat/miette/commit/c3f41b972da0e89220e7d9de08f420912ec8973a))
+
+#### Features
+
+* **protocol:**  sketched out a basic protocol ([e2387ce2](https://github.com/zkat/miette/commit/e2387ce2edd4165d04f47a084f3f1492a5de8d9d))
+* **reporter:**  dummy reporter implementation + tests ([a437f445](https://github.com/zkat/miette/commit/a437f44511768e52cfedd856b5b1432c0716f378))
+* **span:**  make span end optional ([1cb0ad38](https://github.com/zkat/miette/commit/1cb0ad38524696a733f6134092ffd998f76fb142))
+
+
+
+<a name="0.0.0"></a>
+## 0.0.0 (2021-08-03)
+
+Don't mind me, just parking this crate name.
+
+
diff --git a/CODE_OF_CONDUCT.md b/CODE_OF_CONDUCT.md
new file mode 100644
index 0000000..d5aa153
--- /dev/null
+++ b/CODE_OF_CONDUCT.md
@@ -0,0 +1,150 @@
+# Code of Conduct
+
+## When Something Happens
+
+If you see a Code of Conduct violation, follow these steps:
+
+1. Let the person know that what they did is not appropriate and ask them to stop and/or edit their message(s) or commits.
+2. That person should immediately stop the behavior and correct the issue.
+3. If this doesn’t happen, or if you're uncomfortable speaking up, [contact the maintainers](#contacting-maintainers).
+4. As soon as available, a maintainer will look into the issue, and take [further action (see below)](#further-enforcement), starting with a warning, then temporary block, then long-term repo or organization ban.
+
+When reporting, please include any relevant details, links, screenshots, context, or other information that may be used to better understand and resolve the situation.
+
+**The maintainer team will prioritize the well-being and comfort of the recipients of the violation over the comfort of the violator.** See [some examples below](#enforcement-examples).
+
+## Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as contributors and maintainers of this project pledge to making participation in our community a harassment-free experience for everyone, regardless of age, body size, disability, ethnicity, gender identity and expression, level of experience, technical preferences, nationality, personal appearance, race, religion, or sexual identity and orientation.
+
+## Our Standards
+
+Examples of behavior that contributes to creating a positive environment include:
+
+  * Using welcoming and inclusive language.
+  * Being respectful of differing viewpoints and experiences.
+  * Gracefully accepting constructive feedback.
+  * Focusing on what is best for the community.
+  * Showing empathy and kindness towards other community members.
+  * Encouraging and raising up your peers in the project so you can all bask in hacks and glory.
+
+Examples of unacceptable behavior by participants include:
+
+  * The use of sexualized language or imagery and unwelcome sexual attention or advances, including when simulated online. The only exception to sexual topics is channels/spaces specifically for topics of sexual identity.
+  * Casual mention of slavery or indentured servitude and/or false comparisons of one's occupation or situation to slavery. Please consider using or asking about alternate terminology when referring to such metaphors in technology.
+  * Making light of/making mocking comments about trigger warnings and content warnings.
+  * Trolling, insulting/derogatory comments, and personal or political attacks.
+  * Public or private harassment, deliberate intimidation, or threats.
+  * Publishing others' private information, such as a physical or electronic address, without explicit permission. This includes any sort of "outing" of any aspect of someone's identity without their consent.
+  * Publishing private screenshots or quotes of interactions in the context of this project without all quoted users' *explicit* consent.
+  * Publishing of private communication that doesn't have to do with reporting harassment.
+  * Any of the above even when [presented as "ironic" or "joking"](https://en.wikipedia.org/wiki/Hipster_racism).
+  * Any attempt to present "reverse-ism" versions of the above as violations. Examples of reverse-isms are "reverse racism", "reverse sexism", "heterophobia", and "cisphobia".
+  * Unsolicited explanations under the assumption that someone doesn't already know it. Ask before you teach! Don't assume what people's knowledge gaps are.
+  * [Feigning or exaggerating surprise](https://www.recurse.com/manual#no-feigned-surprise) when someone admits to not knowing something.
+  * "[Well-actuallies](https://www.recurse.com/manual#no-well-actuallys)"
+  * Other conduct which could reasonably be considered inappropriate in a professional or community setting.
+
+## Scope
+
+This Code of Conduct applies both within spaces involving this project and in other spaces involving community members. This includes the repository, its Pull Requests and Issue tracker, its Twitter community, private email communications in the context of the project, and any events where members of the project are participating, as well as adjacent communities and venues affecting the project's members.
+
+Depending on the violation, the maintainers may decide that violations of this code of conduct that have happened outside of the scope of the community may deem an individual unwelcome, and take appropriate action to maintain the comfort and safety of its members.
+
+### Other Community Standards
+
+As a project on GitHub, this project is additionally covered by the [GitHub Community Guidelines](https://help.github.com/articles/github-community-guidelines/).
+
+Enforcement of those guidelines after violations overlapping with the above are the responsibility of the entities, and enforcement may happen in any or all of the services/communities.
+
+## Maintainer Enforcement Process
+
+Once the maintainers get involved, they will follow a documented series of steps and do their best to preserve the well-being of project members. This section covers actual concrete steps.
+
+### Contacting Maintainers
+
+You may get in touch with the maintainer team through any of the following methods:
+
+  * Through email:
+    * [coc@zkat.tech](mailto:coc@zkat.tech) (Kat Marchán)
+
+  * Through Twitter:
+    * [@zkat__](https://twitter.com/zkat__) (Kat Marchán)
+
+### Further Enforcement
+
+If you've already followed the [initial enforcement steps](#enforcement), these are the steps maintainers will take for further enforcement, as needed:
+
+  1. Repeat the request to stop.
+  2. If the person doubles down, they will have offending messages removed or edited by a maintainers given an official warning. The PR or Issue may be locked.
+  3. If the behavior continues or is repeated later, the person will be blocked from participating for 24 hours.
+  4. If the behavior continues or is repeated after the temporary block, a long-term (6-12mo) ban will be used.
+
+On top of this, maintainers may remove any offending messages, images, contributions, etc, as they deem necessary.
+
+Maintainers reserve full rights to skip any of these steps, at their discretion, if the violation is considered to be a serious and/or immediate threat to the health and well-being of members of the community. These include any threats, serious physical or verbal attacks, and other such behavior that would be completely unacceptable in any social setting that puts our members at risk.
+
+Members expelled from events or venues with any sort of paid attendance will not be refunded.
+
+### Who Watches the Watchers?
+
+Maintainers and other leaders who do not follow or enforce the Code of Conduct in good faith may face temporary or permanent repercussions as determined by other members of the project's leadership. These may include anything from removal from the maintainer team to a permanent ban from the community.
+
+Additionally, as a project hosted on GitHub, [its own Codes of Conducts may be applied against maintainers of this project](#other-community-standards), externally of this project's procedures.
+
+### Enforcement Examples
+
+#### The Best Case
+
+The vast majority of situations work out like this. This interaction is common, and generally positive.
+
+> Alex: "Yeah I used X and it was really crazy!"
+
+> Patt (not a maintainer): "Hey, could you not use that word? What about 'ridiculous' instead?"
+
+> Alex: "oh sorry, sure." -> edits old comment to say "it was really confusing!"
+
+#### The Maintainer Case
+
+Sometimes, though, you need to get maintainers involved. Maintainers will do their best to resolve conflicts, but people who were harmed by something **will take priority**.
+
+> Patt: "Honestly, sometimes I just really hate using $library and anyone who uses it probably sucks at their job."
+
+> Alex: "Whoa there, could you dial it back a bit? There's a CoC thing about attacking folks' tech use like that."
+
+> Patt: "I'm not attacking anyone, what's your problem?"
+
+> Alex: "@maintainers hey uh. Can someone look at this issue? Patt is getting a bit aggro. I tried to nudge them about it, but nope."
+
+> KeeperOfCommitBits: (on issue) "Hey Patt, maintainer here. Could you tone it down? This sort of attack is really not okay in this space."
+
+> Patt: "Leave me alone I haven't said anything bad wtf is wrong with you."
+
+> KeeperOfCommitBits: (deletes user's comment), "@patt I mean it. Please refer to the CoC over at (URL to this CoC) if you have questions, but you can consider this an actual warning. I'd appreciate it if you reworded your messages in this thread, since they made folks there uncomfortable. Let's try and be kind, yeah?"
+
+> Patt: "@keeperofbits Okay sorry. I'm just frustrated and I'm kinda burnt out and I guess I got carried away. I'll DM Alex a note apologizing and edit my messages. Sorry for the trouble."
+
+> KeeperOfCommitBits: "@patt Thanks for that. I hear you on the stress. Burnout sucks :/.  Have a good one!"
+
+#### The Nope Case
+
+> PepeTheFrog🐸: "Hi, I am a literal actual nazi and I think white supremacists are quite fashionable."
+
+> Patt: "NOOOOPE. OH NOPE NOPE."
+
+> Alex: "JFC NO. NOPE. @keeperofbits NOPE NOPE LOOK HERE"
+
+> KeeperOfCommitBits: "👀 Nope. NOPE NOPE NOPE. 🔥"
+
+> PepeTheFrog🐸 has been banned from all organization or user repositories belonging to KeeperOfCommitBits.
+
+## Attribution
+
+This Code of Conduct was generated using [WeAllJS Code of Conduct Generator](https://npm.im/weallbehave), which is based on the [WeAllJS Code of
+Conduct](https://wealljs.org/code-of-conduct), which is itself based on
+[Contributor Covenant](http://contributor-covenant.org), version 1.4, available
+at
+[http://contributor-covenant.org/version/1/4](http://contributor-covenant.org/version/1/4),
+and the LGBTQ in Technology Slack [Code of
+Conduct](http://lgbtq.technology/coc.html).
+
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644
index 0000000..87215d6
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1,257 @@
+# Contributing
+
+## How do I... <a name="toc"></a>
+
+* [Use This Guide](#introduction)?
+* Ask or Say Something? 🤔🐛😱
+  * [Request Support](#request-support)
+  * [Report an Error or Bug](#report-an-error-or-bug)
+  * [Request a Feature](#request-a-feature)
+* Make Something? 🤓👩🏽‍💻📜🍳
+  * [Project Setup](#project-setup)
+  * [Contribute Documentation](#contribute-documentation)
+  * [Contribute Code](#contribute-code)
+* Manage Something ✅🙆🏼💃👔
+  * [Provide Support on Issues](#provide-support-on-issues)
+  * [Label Issues](#label-issues)
+  * [Clean Up Issues and PRs](#clean-up-issues-and-prs)
+  * [Review Pull Requests](#review-pull-requests)
+  * [Merge Pull Requests](#merge-pull-requests)
+  * [Tag a Release](#tag-a-release)
+  * [Join the Project Team](#join-the-project-team)
+* Add a Guide Like This One [To My Project](#attribution)? 🤖😻👻
+
+## Introduction
+
+Thank you so much for your interest in contributing! All types of contributions are encouraged and valued. See the [table of contents](#toc) for different ways to help and details about how this project handles them!📝
+
+Please make sure to read the relevant section before making your contribution! It will make it a lot easier for us maintainers to make the most of it and smooth out the experience for all involved. 💚
+
+The [Project Team](#join-the-project-team) looks forward to your contributions. 🙌🏾✨
+
+## Request Support
+
+If you have a question about this project, how to use it, or just need clarification about something:
+
+* Open an Issue at https://github.com/zkat/miette/issues
+* Provide as much context as you can about what you're running into.
+* Provide project and platform versions, depending on what seems relevant. If not, please be ready to provide that information if maintainers ask for it.
+
+Once it's filed:
+
+* The project team will [label the issue](#label-issues).
+* Someone will try to have a response soon.
+* If you or the maintainers don't respond to an issue for 30 days, the [issue will be closed](#clean-up-issues-and-prs). If you want to come back to it, reply (once, please), and we'll reopen the existing issue. Please avoid filing new issues as extensions of one you already made.
+
+## Report an Error or Bug
+
+If you run into an error or bug with the project:
+
+* Open an Issue at https://github.com/zkat/miette/issues
+* Include *reproduction steps* that someone else can follow to recreate the bug or error on their own.
+* Provide project and platform versions, depending on what seems relevant. If not, please be ready to provide that information if maintainers ask for it.
+
+Once it's filed:
+
+* The project team will [label the issue](#label-issues).
+* A team member will try to reproduce the issue with your provided steps. If there are no repro steps or no obvious way to reproduce the issue, the team will ask you for those steps and mark the issue as `needs-repro`. Bugs with the `needs-repro` tag will not be addressed until they are reproduced.
+* If the team is able to reproduce the issue, it will be marked `needs-fix`, as well as possibly other tags (such as `critical`), and the issue will be left to be [implemented by someone](#contribute-code).
+* If you or the maintainers don't respond to an issue for 30 days, the [issue will be closed](#clean-up-issues-and-prs). If you want to come back to it, reply (once, please), and we'll reopen the existing issue. Please avoid filing new issues as extensions of one you already made.
+* `critical` issues may be left open, depending on perceived immediacy and severity, even past the 30 day deadline.
+
+## Request a Feature
+
+If the project doesn't do something you need or want it to do:
+
+* Open an Issue at https://github.com/zkat/miette/issues
+* Provide as much context as you can about what you're running into.
+* Please try and be clear about why existing features and alternatives would not work for you.
+
+Once it's filed:
+
+* The project team will [label the issue](#label-issues).
+* The project team will evaluate the feature request, possibly asking you more questions to understand its purpose and any relevant requirements. If the issue is closed, the team will convey their reasoning and suggest an alternative path forward.
+* If the feature request is accepted, it will be marked for implementation with `feature-accepted`, which can then be done by either by a core team member or by anyone in the community who wants to [contribute code](#contribute-code).
+
+Note: The team is unlikely to be able to accept every single feature request that is filed. Please understand if they need to say no.
+
+## Project Setup
+
+So you wanna contribute some code! That's great! This project uses GitHub Pull Requests to manage contributions, so [read up on how to fork a GitHub project and file a PR](https://guides.github.com/activities/forking) if you've never done it before.
+
+If this seems like a lot or you aren't able to do all this setup, you might also be able to [edit the files directly](https://help.github.com/articles/editing-files-in-another-user-s-repository/) without having to do any of this setup. Yes, [even code](#contribute-code).
+
+If you want to go the usual route and run the project locally, though:
+
+* [Install Rust](https://www.rust-lang.org/learn/get-started)
+* [Fork the project](https://guides.github.com/activities/forking/#fork)
+
+Then in your terminal:
+* `cd path/to/your/clone`
+* `cargo test --features fancy`
+
+And you should be ready to go!
+
+**Note:** If you don't include the "fancy" feature, one of the doc-tests will fail.
+
+## Contribute Documentation
+
+Documentation is a super important, critical part of this project. Docs are how we keep track of what we're doing, how, and why. It's how we stay on the same page about our policies. And it's how we tell others everything they need in order to be able to use this project -- or contribute to it. So thank you in advance.
+
+Documentation contributions of any size are welcome! Feel free to file a PR even if you're just rewording a sentence to be more clear, or fixing a spelling mistake!
+
+To contribute documentation:
+
+* [Set up the project](#project-setup).
+* Edit or add any relevant documentation.
+* Make sure your changes are formatted correctly and consistently with the rest of the documentation.
+* Re-read what you wrote, and run a spellchecker on it to make sure you didn't miss anything.
+* Write clear, concise commit message(s) using [conventional-changelog format](https://github.com/conventional-changelog/conventional-changelog-angular/blob/master/convention.md). Documentation commits should use `docs(<component>): <message>`.
+* Go to https://github.com/zkat/miette/pulls and open a new pull request with your changes.
+* If your PR is connected to an open issue, add a line in your PR's description that says `Fixes: #123`, where `#123` is the number of the issue you're fixing.
+
+Once you've filed the PR:
+
+* One or more maintainers will use GitHub's review feature to review your PR.
+* If the maintainer asks for any changes, edit your changes, push, and ask for another review.
+* If the maintainer decides to pass on your PR, they will thank you for the contribution and explain why they won't be accepting the changes. That's ok! We still really appreciate you taking the time to do it, and we don't take that lightly. 💚
+* If your PR gets accepted, it will be marked as such, and merged into the `latest` branch soon after. Your contribution will be distributed to the masses next time the maintainers [tag a release](#tag-a-release)
+
+## Contribute Code
+
+We like code commits a lot! They're super handy, and they keep the project going and doing the work it needs to do to be useful to others.
+
+Code contributions of just about any size are acceptable!
+
+The main difference between code contributions and documentation contributions is that contributing code requires inclusion of relevant tests for the code being added or changed. Contributions without accompanying tests will be held off until a test is added, unless the maintainers consider the specific tests to be either impossible, or way too much of a burden for such a contribution.
+
+To contribute code:
+
+* [Set up the project](#project-setup).
+* Make any necessary changes to the source code.
+* Include any [additional documentation](#contribute-documentation) the changes might need.
+* Write tests that verify that your contribution works as expected.
+* Write clear, concise commit message(s) using [conventional-changelog format](https://github.com/conventional-changelog/conventional-changelog-angular/blob/master/convention.md).
+* Dependency updates, additions, or removals must be in individual commits, and the message must use the format: `<prefix>(deps): PKG@VERSION`, where `<prefix>` is any of the usual `conventional-changelog` prefixes, at your discretion.
+* Go to https://github.com/zkat/miette/pulls and open a new pull request with your changes.
+* If your PR is connected to an open issue, add a line in your PR's description that says `Fixes: #123`, where `#123` is the number of the issue you're fixing.
+
+Once you've filed the PR:
+
+* Barring special circumstances, maintainers will not review PRs until all checks pass (Travis, AppVeyor, etc).
+* One or more maintainers will use GitHub's review feature to review your PR.
+* If the maintainer asks for any changes, edit your changes, push, and ask for another review. Additional tags (such as `needs-tests`) will be added depending on the review.
+* If the maintainer decides to pass on your PR, they will thank you for the contribution and explain why they won't be accepting the changes. That's ok! We still really appreciate you taking the time to do it, and we don't take that lightly. 💚
+* If your PR gets accepted, it will be marked as such, and merged into the `latest` branch soon after. Your contribution will be distributed to the masses next time the maintainers [tag a release](#tag-a-release)
+
+## Provide Support on Issues
+
+[Needs Collaborator](#join-the-project-team): none
+
+Helping out other users with their questions is a really awesome way of contributing to any community. It's not uncommon for most of the issues on an open source projects being support-related questions by users trying to understand something they ran into, or find their way around a known bug.
+
+Sometimes, the `support` label will be added to things that turn out to actually be other things, like bugs or feature requests. In that case, suss out the details with the person who filed the original issue, add a comment explaining what the bug is, and change the label from `support` to `bug` or `feature`. If you can't do this yourself, @mention a maintainer so they can do it.
+
+In order to help other folks out with their questions:
+
+* Go to the issue tracker and [filter open issues by the `support` label](https://github.com/zkat/miette/issues?q=is%3Aopen+is%3Aissue+label%3Asupport).
+* Read through the list until you find something that you're familiar enough with to give an answer to.
+* Respond to the issue with whatever details are needed to clarify the question, or get more details about what's going on.
+* Once the discussion wraps up and things are clarified, either close the issue, or ask the original issue filer (or a maintainer) to close it for you.
+
+Some notes on picking up support issues:
+
+* Avoid responding to issues you don't know you can answer accurately.
+* As much as possible, try to refer to past issues with accepted answers. Link to them from your replies with the `#123` format.
+* Be kind and patient with users -- often, folks who have run into confusing things might be upset or impatient. This is ok. Try to understand where they're coming from, and if you're too uncomfortable with the tone, feel free to stay away or withdraw from the issue. (note: if the user is outright hostile or is violating the CoC, [refer to the Code of Conduct](CODE_OF_CONDUCT.md) to resolve the conflict).
+
+## Label Issues
+
+[Needs Collaborator](#join-the-project-team): Issue Tracker
+
+One of the most important tasks in handling issues is labeling them usefully and accurately. All other tasks involving issues ultimately rely on the issue being classified in such a way that relevant parties looking to do their own tasks can find them quickly and easily.
+
+In order to label issues, [open up the list of unlabeled issues](https://github.com/zkat/miette/issues?q=is%3Aopen+is%3Aissue+no%3Alabel) and, **from newest to oldest**, read through each one and apply issue labels according to the table below. If you're unsure about what label to apply, skip the issue and try the next one: don't feel obligated to label each and every issue yourself!
+
+Label | Apply When | Notes
+--- | --- | ---
+`bug` | Cases where the code (or documentation) is behaving in a way it wasn't intended to. | If something is happening that surprises the *user* but does not go against the way the code is designed, it should use the `enhancement` label.
+`critical` | Added to `bug` issues if the problem described makes the code completely unusable in a common situation. |
+`documentation` | Added to issues or pull requests that affect any of the documentation for the project. | Can be combined with other labels, such as `bug` or `enhancement`.
+`duplicate` | Added to issues or PRs that refer to the exact same issue as another one that's been previously labeled. | Duplicate issues should be marked and closed right away, with a message referencing the issue it's a duplicate of (with `#123`)
+`enhancement` | Added to [feature requests](#request-a-feature), PRs, or documentation issues that are purely additive: the code or docs currently work as expected, but a change is being requested or suggested. |
+`help wanted` | Applied by [Committers](#join-the-project-team) to issues and PRs that they would like to get outside help for. Generally, this means it's lower priority for the maintainer team to itself implement, but that the community is encouraged to pick up if they so desire | Never applied on first-pass labeling.
+`in-progress` | Applied by [Committers](#join-the-project-team) to PRs that are pending some work before they're ready for review. | The original PR submitter should @mention the team member that applied the label once the PR is complete.
+`performance` | This issue or PR is directly related to improving performance. |
+`refactor` | Added to issues or PRs that deal with cleaning up or modifying the project for the betterment of it. |
+`starter` | Applied by [Committers](#join-the-project-team) to issues that they consider good introductions to the project for people who have not contributed before. These are not necessarily "easy", but rather focused around how much context is necessary in order to understand what needs to be done for this project in particular. | Existing project members are expected to stay away from these unless they increase in priority.
+`support` | This issue is either asking a question about how to use the project, clarifying the reason for unexpected behavior, or possibly reporting a `bug` but does not have enough detail yet to determine whether it would count as such. | The label should be switched to `bug` if reliable reproduction steps are provided. Issues primarily with unintended configurations of a user's environment are not considered bugs, even if they cause crashes.
+`tests` | This issue or PR either requests or adds primarily tests to the project. | If a PR is pending tests, that will be handled through the [PR review process](#review-pull-requests)
+`wontfix` | Labelers may apply this label to issues that clearly have nothing at all to do with the project or are otherwise entirely outside of its scope/sphere of influence. [Committers](#join-the-project-team) may apply this label and close an issue or PR if they decide to pass on an otherwise relevant issue. | The issue or PR should be closed as soon as the label is applied, and a clear explanation provided of why the label was used. Contributors are free to contest the labeling, but the decision ultimately falls on committers as to whether to accept something or not.
+
+## Clean Up Issues and PRs
+
+[Needs Collaborator](#join-the-project-team): Issue Tracker
+
+Issues and PRs can go stale after a while. Maybe they're abandoned. Maybe the team will just plain not have time to address them any time soon.
+
+In these cases, they should be closed until they're brought up again or the interaction starts over.
+
+To clean up issues and PRs:
+
+* Search the issue tracker for issues or PRs, and add the term `updated:<=YYYY-MM-DD`, where the date is 30 days before today.
+* Go through each issue *from oldest to newest*, and close them if **all of the following are true**:
+  * not opened by a maintainer
+  * not marked as `critical`
+  * not marked as `starter` or `help wanted` (these might stick around for a while, in general, as they're intended to be available)
+  * no explicit messages in the comments asking for it to be left open
+  * does not belong to a milestone
+* Leave a message when closing saying "Cleaning up stale issue. Please reopen or ping us if and when you're ready to resume this. See https://github.com/zkat/miette/blob/latest/CONTRIBUTING.md#clean-up-issues-and-prs for more details."
+
+## Review Pull Requests
+
+[Needs Collaborator](#join-the-project-team): Issue Tracker
+
+While anyone can comment on a PR, add feedback, etc, PRs are only *approved* by team members with Issue Tracker or higher permissions.
+
+PR reviews use [GitHub's own review feature](https://help.github.com/articles/about-pull-request-reviews/), which manages comments, approval, and review iteration.
+
+Some notes:
+
+* You may ask for minor changes ("nitpicks"), but consider whether they are really blockers to merging: try to err on the side of "approve, with comments".
+* *ALL PULL REQUESTS* should be covered by a test: either by a previously-failing test, an existing test that covers the entire functionality of the submitted code, or new tests to verify any new/changed behavior. All tests must also pass and follow established conventions. Test coverage should not drop, unless the specific case is considered reasonable by maintainers.
+* Please make sure you're familiar with the code or documentation being updated, unless it's a minor change (spellchecking, minor formatting, etc). You may @mention another project member who you think is better suited for the review, but still provide a non-approving review of your own.
+* Be extra kind: people who submit code/doc contributions are putting themselves in a pretty vulnerable position, and have put time and care into what they've done (even if that's not obvious to you!) -- always respond with respect, be understanding, but don't feel like you need to sacrifice your standards for their sake, either. Just don't be a jerk about it?
+
+## Merge Pull Requests
+
+[Needs Collaborator](#join-the-project-team): Committer
+
+TBD - need to hash out a bit more of this process.
+
+## Tag A Release
+
+[Needs Collaborator](#join-the-project-team): Committer
+
+TBD - need to hash out a bit more of this process. The most important bit here is probably that all tests must pass, and tags must use [semver](https://semver.org).
+
+## Join the Project Team
+
+### Ways to Join
+
+There are many ways to contribute! Most of them don't require any official status unless otherwise noted. That said, there's a couple of positions that grant special repository abilities, and this section describes how they're granted and what they do.
+
+All of the below positions are granted based on the project team's needs, as well as their consensus opinion about whether they would like to work with the person and think that they would fit well into that position. The process is relatively informal, and it's likely that people who express interest in participating can just be granted the permissions they'd like.
+
+You can spot a collaborator on the repo by looking for the `[Collaborator]` or `[Owner]` tags next to their names.
+
+Permission | Description
+--- | ---
+Issue Tracker | Granted to contributors who express a strong interest in spending time on the project's issue tracker. These tasks are mainly [labeling issues](#label-issues), [cleaning up old ones](#clean-up-issues-and-prs), and [reviewing pull requests](#review-pull-requests), as well as all the usual things non-team-member contributors can do. Issue handlers should not merge pull requests, tag releases, or directly commit code themselves: that should still be done through the usual pull request process. Becoming an Issue Handler means the project team trusts you to understand enough of the team's process and context to implement it on the issue tracker.
+Committer | Granted to contributors who want to handle the actual pull request merges, tagging new versions, etc. Committers should have a good level of familiarity with the codebase, and enough context to understand the implications of various changes, as well as a good sense of the will and expectations of the project team.
+Admin/Owner | Granted to people ultimately responsible for the project, its community, etc.
+
+## Attribution
+
+This guide was generated using the WeAllJS `CONTRIBUTING.md` generator. [Make your own](https://npm.im/weallcontribute)!
+
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..712a834
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,132 @@
+# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
+#
+# When uploading crates to the registry Cargo will automatically
+# "normalize" Cargo.toml files for maximal compatibility
+# with all versions of Cargo and also rewrite `path` dependencies
+# to registry (e.g., crates.io) dependencies.
+#
+# If you are reading this file be aware that the original Cargo.toml
+# will likely look very different (and much more reasonable).
+# See Cargo.toml.orig for the original contents.
+
+[package]
+edition = "2018"
+rust-version = "1.56.0"
+name = "miette"
+version = "5.9.0"
+authors = ["Kat Marchán <kzm@zkat.tech>"]
+exclude = [
+    "images/",
+    "tests/",
+    "miette-derive/",
+]
+description = "Fancy diagnostic reporting library and protocol for us mere mortals who aren't compiler hackers."
+documentation = "https://docs.rs/miette"
+readme = "README.md"
+categories = ["rust-patterns"]
+license = "Apache-2.0"
+repository = "https://github.com/zkat/miette"
+
+[package.metadata.docs.rs]
+all-features = true
+
+[dependencies.backtrace]
+version = "0.3.61"
+optional = true
+
+[dependencies.backtrace-ext]
+version = "0.2.1"
+optional = true
+
+[dependencies.is-terminal]
+version = "0.4.0"
+optional = true
+
+[dependencies.miette-derive]
+version = "=5.9.0"
+
+[dependencies.once_cell]
+version = "1.8.0"
+
+[dependencies.owo-colors]
+version = "3.0.0"
+optional = true
+
+[dependencies.serde]
+version = "1.0.162"
+features = ["derive"]
+optional = true
+
+[dependencies.supports-color]
+version = "2.0.0"
+optional = true
+
+[dependencies.supports-hyperlinks]
+version = "2.0.0"
+optional = true
+
+[dependencies.supports-unicode]
+version = "2.0.0"
+optional = true
+
+[dependencies.terminal_size]
+version = "0.1.17"
+optional = true
+
+[dependencies.textwrap]
+version = "0.15.0"
+optional = true
+
+[dependencies.thiserror]
+version = "1.0.40"
+
+[dependencies.unicode-width]
+version = "0.1.9"
+
+[dev-dependencies.futures]
+version = "0.3"
+default-features = false
+
+[dev-dependencies.indenter]
+version = "0.3.0"
+
+[dev-dependencies.lazy_static]
+version = "1.4"
+
+[dev-dependencies.regex]
+version = "1.5"
+
+[dev-dependencies.rustversion]
+version = "1.0"
+
+[dev-dependencies.semver]
+version = "1.0.4"
+
+[dev-dependencies.serde_json]
+version = "1.0.64"
+
+[dev-dependencies.syn]
+version = "2.0"
+features = ["full"]
+
+[dev-dependencies.trybuild]
+version = "1.0.19"
+features = ["diff"]
+
+[features]
+default = []
+fancy = [
+    "fancy-no-backtrace",
+    "backtrace",
+    "backtrace-ext",
+]
+fancy-no-backtrace = [
+    "owo-colors",
+    "is-terminal",
+    "textwrap",
+    "terminal_size",
+    "supports-hyperlinks",
+    "supports-color",
+    "supports-unicode",
+]
+no-format-args-capture = []
diff --git a/Cargo.toml.orig b/Cargo.toml.orig
new file mode 100644
index 0000000..160556f
--- /dev/null
+++ b/Cargo.toml.orig
@@ -0,0 +1,64 @@
+[package]
+name = "miette"
+version = "5.9.0"
+authors = ["Kat Marchán <kzm@zkat.tech>"]
+description = "Fancy diagnostic reporting library and protocol for us mere mortals who aren't compiler hackers."
+categories = ["rust-patterns"]
+repository = "https://github.com/zkat/miette"
+documentation = "https://docs.rs/miette"
+license = "Apache-2.0"
+readme = "README.md"
+edition = "2018"
+rust-version = "1.56.0"
+exclude = ["images/", "tests/", "miette-derive/"]
+
+[dependencies]
+thiserror = "1.0.40"
+miette-derive = { path = "miette-derive", version = "=5.9.0" }
+once_cell = "1.8.0"
+unicode-width = "0.1.9"
+
+owo-colors = { version = "3.0.0", optional = true }
+is-terminal = { version = "0.4.0", optional = true }
+textwrap = { version = "0.15.0", optional = true }
+supports-hyperlinks = { version = "2.0.0", optional = true }
+supports-color = { version = "2.0.0", optional = true }
+supports-unicode = { version = "2.0.0", optional = true }
+backtrace = { version = "0.3.61", optional = true }
+terminal_size = { version = "0.1.17", optional = true }
+backtrace-ext = { version = "0.2.1", optional = true }
+serde = { version = "1.0.162", features = ["derive"], optional = true }
+
+[dev-dependencies]
+semver = "1.0.4"
+
+# Eyre devdeps
+futures = { version = "0.3", default-features = false }
+indenter = "0.3.0"
+rustversion = "1.0"
+trybuild = { version = "1.0.19", features = ["diff"] }
+syn = { version = "2.0", features = ["full"] }
+regex = "1.5"
+lazy_static = "1.4"
+
+serde_json = "1.0.64"
+
+[features]
+default = []
+no-format-args-capture = []
+fancy-no-backtrace = [
+    "owo-colors",
+    "is-terminal",
+    "textwrap",
+    "terminal_size",
+    "supports-hyperlinks",
+    "supports-color",
+    "supports-unicode",
+]
+fancy = ["fancy-no-backtrace", "backtrace", "backtrace-ext"]
+
+[workspace]
+members = ["miette-derive"]
+
+[package.metadata.docs.rs]
+all-features = true
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..d645695
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,202 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
diff --git a/METADATA b/METADATA
new file mode 100644
index 0000000..873e6bd
--- /dev/null
+++ b/METADATA
@@ -0,0 +1,19 @@
+name: "miette"
+description: "Fancy diagnostic reporting library and protocol for us mere mortals who aren\'t compiler hackers."
+third_party {
+  url {
+    type: HOMEPAGE
+    value: "https://crates.io/crates/miette"
+  }
+  url {
+    type: ARCHIVE
+    value: "https://static.crates.io/crates/miette/miette-5.9.0.crate"
+  }
+  version: "5.9.0"
+  license_type: NOTICE
+  last_upgrade_date {
+    year: 2023
+    month: 6
+    day: 12
+  }
+}
diff --git a/MODULE_LICENSE_APACHE2 b/MODULE_LICENSE_APACHE2
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/MODULE_LICENSE_APACHE2
diff --git a/Makefile.toml b/Makefile.toml
new file mode 100644
index 0000000..a849d91
--- /dev/null
+++ b/Makefile.toml
@@ -0,0 +1,17 @@
+[tasks.changelog]
+workspace=false
+install_crate="git-cliff"
+command = "git-cliff"
+args = ["--prepend", "CHANGELOG.md", "-u", "--tag", "${@}"]
+
+[tasks.release]
+workspace=false
+install_crate="cargo-release"
+command = "cargo"
+args = ["release", "--workspace", "${@}"]
+
+[tasks.readme]
+workspace=false
+install_crate="cargo-readme"
+command = "cargo"
+args = ["readme", "-o", "README.md"]
diff --git a/OWNERS b/OWNERS
new file mode 100644
index 0000000..45dc4dd
--- /dev/null
+++ b/OWNERS
@@ -0,0 +1 @@
+include platform/prebuilts/rust:master:/OWNERS
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..ff25b3a
--- /dev/null
+++ b/README.md
@@ -0,0 +1,654 @@
+
+# `miette`
+
+You run miette? You run her code like the software? Oh. Oh! Error code for
+coder! Error code for One Thousand Lines!
+
+## About
+
+`miette` is a diagnostic library for Rust. It includes a series of
+traits/protocols that allow you to hook into its error reporting facilities,
+and even write your own error reports! It lets you define error types that
+can print out like this (or in any format you like!):
+
+<img src="https://raw.githubusercontent.com/zkat/miette/main/images/serde_json.png" alt="Hi! miette also includes a screen-reader-oriented diagnostic printer that's enabled in various situations, such as when you use NO_COLOR or CLICOLOR settings, or on CI. This behavior is also fully configurable and customizable. For example, this is what this particular diagnostic will look like when the narrated printer is enabled:
+\
+Error: Received some bad JSON from the source. Unable to parse.
+    Caused by: missing field `foo` at line 1 column 1700
+\
+Begin snippet for https://api.nuget.org/v3/registration5-gz-semver2/json.net/index.json starting
+at line 1, column 1659
+\
+snippet line 1: gs&quot;:[&quot;json&quot;],&quot;title&quot;:&quot;&quot;,&quot;version&quot;:&quot;1.0.0&quot;},&quot;packageContent&quot;:&quot;https://api.nuget.o
+    highlight starting at line 1, column 1699: last parsing location
+\
+diagnostic help: This is a bug. It might be in ruget, or it might be in the
+source you're using, but it's definitely a bug and should be reported.
+diagnostic error code: ruget::api::bad_json
+" />
+
+> **NOTE: You must enable the `"fancy"` crate feature to get fancy report
+output like in the screenshots above.** You should only do this in your
+toplevel crate, as the fancy feature pulls in a number of dependencies that
+libraries and such might not want.
+
+## Table of Contents <!-- omit in toc -->
+
+- [About](#about)
+- [Features](#features)
+- [Installing](#installing)
+- [Example](#example)
+- [Using](#using)
+  - [... in libraries](#-in-libraries)
+  - [... in application code](#-in-application-code)
+  - [... in `main()`](#-in-main)
+  - [... diagnostic code URLs](#-diagnostic-code-urls)
+  - [... snippets](#-snippets)
+  - [... multiple related errors](#-multiple-related-errors)
+  - [... delayed source code](#-delayed-source-code)
+  - [... handler options](#-handler-options)
+  - [... dynamic diagnostics](#-dynamic-diagnostics)
+- [Acknowledgements](#acknowledgements)
+- [License](#license)
+
+## Features
+
+- Generic [`Diagnostic`] protocol, compatible (and dependent on)
+  [`std::error::Error`].
+- Unique error codes on every [`Diagnostic`].
+- Custom links to get more details on error codes.
+- Super handy derive macro for defining diagnostic metadata.
+- Replacements for [`anyhow`](https://docs.rs/anyhow)/[`eyre`](https://docs.rs/eyre)
+  types [`Result`], [`Report`] and the [`miette!`] macro for the
+  `anyhow!`/`eyre!` macros.
+- Generic support for arbitrary [`SourceCode`]s for snippet data, with
+  default support for `String`s included.
+
+The `miette` crate also comes bundled with a default [`ReportHandler`] with
+the following features:
+
+- Fancy graphical [diagnostic output](#about), using ANSI/Unicode text
+- single- and multi-line highlighting support
+- Screen reader/braille support, gated on [`NO_COLOR`](http://no-color.org/),
+  and other heuristics.
+- Fully customizable graphical theming (or overriding the printers
+  entirely).
+- Cause chain printing
+- Turns diagnostic codes into links in [supported terminals](https://gist.github.com/egmontkob/eb114294efbcd5adb1944c9f3cb5feda).
+
+## Installing
+
+```sh
+$ cargo add miette
+```
+
+If you want to use the fancy printer in all these screenshots:
+
+```sh
+$ cargo add miette --features fancy
+```
+
+## Example
+
+```rust
+/*
+You can derive a `Diagnostic` from any `std::error::Error` type.
+
+`thiserror` is a great way to define them, and plays nicely with `miette`!
+*/
+use miette::{Diagnostic, SourceSpan};
+use thiserror::Error;
+
+#[derive(Error, Debug, Diagnostic)]
+#[error("oops!")]
+#[diagnostic(
+    code(oops::my::bad),
+    url(docsrs),
+    help("try doing it better next time?")
+)]
+struct MyBad {
+    // The Source that we're gonna be printing snippets out of.
+    // This can be a String if you don't have or care about file names.
+    #[source_code]
+    src: NamedSource,
+    // Snippets and highlights can be included in the diagnostic!
+    #[label("This bit here")]
+    bad_bit: SourceSpan,
+}
+
+/*
+Now let's define a function!
+
+Use this `Result` type (or its expanded version) as the return type
+throughout your app (but NOT your libraries! Those should always return
+concrete types!).
+*/
+use miette::{NamedSource, Result};
+fn this_fails() -> Result<()> {
+    // You can use plain strings as a `Source`, or anything that implements
+    // the one-method `Source` trait.
+    let src = "source\n  text\n    here".to_string();
+    let len = src.len();
+
+    Err(MyBad {
+        src: NamedSource::new("bad_file.rs", src),
+        bad_bit: (9, 4).into(),
+    })?;
+
+    Ok(())
+}
+
+/*
+Now to get everything printed nicely, just return a `Result<()>`
+and you're all set!
+
+Note: You can swap out the default reporter for a custom one using
+`miette::set_hook()`
+*/
+fn pretend_this_is_main() -> Result<()> {
+    // kaboom~
+    this_fails()?;
+
+    Ok(())
+}
+```
+
+And this is the output you'll get if you run this program:
+
+<img src="https://raw.githubusercontent.com/zkat/miette/main/images/single-line-example.png" alt="
+Narratable printout:
+\
+Error: Types mismatched for operation.
+    Diagnostic severity: error
+Begin snippet starting at line 1, column 1
+\
+snippet line 1: 3 + &quot;5&quot;
+    label starting at line 1, column 1: int
+    label starting at line 1, column 1: doesn't support these values.
+    label starting at line 1, column 1: string
+diagnostic help: Change int or string to be the right types and try again.
+diagnostic code: nu::parser::unsupported_operation
+For more details, see https://docs.rs/nu-parser/0.1.0/nu-parser/enum.ParseError.html#variant.UnsupportedOperation">
+
+## Using
+
+### ... in libraries
+
+`miette` is _fully compatible_ with library usage. Consumers who don't know
+about, or don't want, `miette` features can safely use its error types as
+regular [`std::error::Error`].
+
+We highly recommend using something like [`thiserror`](https://docs.rs/thiserror)
+to define unique error types and error wrappers for your library.
+
+While `miette` integrates smoothly with `thiserror`, it is _not required_.
+If you don't want to use the [`Diagnostic`] derive macro, you can implement
+the trait directly, just like with `std::error::Error`.
+
+```rust
+// lib/error.rs
+use miette::Diagnostic;
+use thiserror::Error;
+
+#[derive(Error, Diagnostic, Debug)]
+pub enum MyLibError {
+    #[error(transparent)]
+    #[diagnostic(code(my_lib::io_error))]
+    IoError(#[from] std::io::Error),
+
+    #[error("Oops it blew up")]
+    #[diagnostic(code(my_lib::bad_code))]
+    BadThingHappened,
+}
+```
+
+Then, return this error type from all your fallible public APIs. It's a best
+practice to wrap any "external" error types in your error `enum` instead of
+using something like [`Report`] in a library.
+
+### ... in application code
+
+Application code tends to work a little differently than libraries. You
+don't always need or care to define dedicated error wrappers for errors
+coming from external libraries and tools.
+
+For this situation, `miette` includes two tools: [`Report`] and
+[`IntoDiagnostic`]. They work in tandem to make it easy to convert regular
+`std::error::Error`s into [`Diagnostic`]s. Additionally, there's a
+[`Result`] type alias that you can use to be more terse.
+
+When dealing with non-`Diagnostic` types, you'll want to
+`.into_diagnostic()` them:
+
+```rust
+// my_app/lib/my_internal_file.rs
+use miette::{IntoDiagnostic, Result};
+use semver::Version;
+
+pub fn some_tool() -> Result<Version> {
+    Ok("1.2.x".parse().into_diagnostic()?)
+}
+```
+
+`miette` also includes an `anyhow`/`eyre`-style `Context`/`WrapErr` traits
+that you can import to add ad-hoc context messages to your `Diagnostic`s, as
+well, though you'll still need to use `.into_diagnostic()` to make use of
+it:
+
+```rust
+// my_app/lib/my_internal_file.rs
+use miette::{IntoDiagnostic, Result, WrapErr};
+use semver::Version;
+
+pub fn some_tool() -> Result<Version> {
+    Ok("1.2.x"
+        .parse()
+        .into_diagnostic()
+        .wrap_err("Parsing this tool's semver version failed.")?)
+}
+```
+
+To construct your own simple adhoc error use the [`miette!`] macro:
+
+```rust
+// my_app/lib/my_internal_file.rs
+use miette::{miette, IntoDiagnostic, Result, WrapErr};
+use semver::Version;
+
+pub fn some_tool() -> Result<Version> {
+    let version = "1.2.x";
+    Ok(version
+        .parse()
+        .map_err(|_| miette!("Invalid version {}", version))?)
+}
+```
+
+### ... in `main()`
+
+`main()` is just like any other part of your application-internal code. Use
+`Result` as your return value, and it will pretty-print your diagnostics
+automatically.
+
+> **NOTE:** You must enable the `"fancy"` crate feature to get fancy report
+output like in the screenshots here.** You should only do this in your
+toplevel crate, as the fancy feature pulls in a number of dependencies that
+libraries and such might not want.
+
+```rust
+use miette::{IntoDiagnostic, Result};
+use semver::Version;
+
+fn pretend_this_is_main() -> Result<()> {
+    let version: Version = "1.2.x".parse().into_diagnostic()?;
+    println!("{}", version);
+    Ok(())
+}
+```
+
+Please note: in order to get fancy diagnostic rendering with all the pretty
+colors and arrows, you should install `miette` with the `fancy` feature
+enabled:
+
+```toml
+miette = { version = "X.Y.Z", features = ["fancy"] }
+```
+
+### ... diagnostic code URLs
+
+`miette` supports providing a URL for individual diagnostics. This URL will
+be displayed as an actual link in supported terminals, like so:
+
+<img
+src="https://raw.githubusercontent.com/zkat/miette/main/images/code_linking.png"
+alt=" Example showing the graphical report printer for miette
+pretty-printing an error code. The code is underlined and followed by text
+saying to 'click here'. A hover tooltip shows a full-fledged URL that can be
+Ctrl+Clicked to open in a browser.
+\
+This feature is also available in the narratable printer. It will add a line
+after printing the error code showing a plain URL that you can visit.
+">
+
+To use this, you can add a `url()` sub-param to your `#[diagnostic]`
+attribute:
+
+```rust
+use miette::Diagnostic;
+use thiserror::Error;
+
+#[derive(Error, Diagnostic, Debug)]
+#[error("kaboom")]
+#[diagnostic(
+    code(my_app::my_error),
+    // You can do formatting!
+    url("https://my_website.com/error_codes#{}", self.code().unwrap())
+)]
+struct MyErr;
+```
+
+Additionally, if you're developing a library and your error type is exported
+from your crate's top level, you can use a special `url(docsrs)` option
+instead of manually constructing the URL. This will automatically create a
+link to this diagnostic on `docs.rs`, so folks can just go straight to your
+(very high quality and detailed!) documentation on this diagnostic:
+
+```rust
+use miette::Diagnostic;
+use thiserror::Error;
+
+#[derive(Error, Diagnostic, Debug)]
+#[diagnostic(
+    code(my_app::my_error),
+    // Will link users to https://docs.rs/my_crate/0.0.0/my_crate/struct.MyErr.html
+    url(docsrs)
+)]
+#[error("kaboom")]
+struct MyErr;
+```
+
+### ... snippets
+
+Along with its general error handling and reporting features, `miette` also
+includes facilities for adding error spans/annotations/labels to your
+output. This can be very useful when an error is syntax-related, but you can
+even use it to print out sections of your own source code!
+
+To achieve this, `miette` defines its own lightweight [`SourceSpan`] type.
+This is a basic byte-offset and length into an associated [`SourceCode`]
+and, along with the latter, gives `miette` all the information it needs to
+pretty-print some snippets! You can also use your own `Into<SourceSpan>`
+types as label spans.
+
+The easiest way to define errors like this is to use the
+`derive(Diagnostic)` macro:
+
+```rust
+use miette::{Diagnostic, SourceSpan};
+use thiserror::Error;
+
+#[derive(Diagnostic, Debug, Error)]
+#[error("oops")]
+#[diagnostic(code(my_lib::random_error))]
+pub struct MyErrorType {
+    // The `Source` that miette will use.
+    #[source_code]
+    src: String,
+
+    // This will underline/mark the specific code inside the larger
+    // snippet context.
+    #[label = "This is the highlight"]
+    err_span: SourceSpan,
+
+    // You can add as many labels as you want.
+    // They'll be rendered sequentially.
+    #[label("This is bad")]
+    snip2: (usize, usize), // `(usize, usize)` is `Into<SourceSpan>`!
+
+    // Snippets can be optional, by using Option:
+    #[label("some text")]
+    snip3: Option<SourceSpan>,
+
+    // with or without label text
+    #[label]
+    snip4: Option<SourceSpan>,
+}
+```
+
+#### ... help text
+`miette` provides two facilities for supplying help text for your errors:
+
+The first is the `#[help()]` format attribute that applies to structs or
+enum variants:
+
+```rust
+use miette::Diagnostic;
+use thiserror::Error;
+
+#[derive(Debug, Diagnostic, Error)]
+#[error("welp")]
+#[diagnostic(help("try doing this instead"))]
+struct Foo;
+```
+
+The other is by programmatically supplying the help text as a field to
+your diagnostic:
+
+```rust
+use miette::Diagnostic;
+use thiserror::Error;
+
+#[derive(Debug, Diagnostic, Error)]
+#[error("welp")]
+#[diagnostic()]
+struct Foo {
+    #[help]
+    advice: Option<String>, // Can also just be `String`
+}
+
+let err = Foo {
+    advice: Some("try doing this instead".to_string()),
+};
+```
+
+### ... multiple related errors
+
+`miette` supports collecting multiple errors into a single diagnostic, and
+printing them all together nicely.
+
+To do so, use the `#[related]` tag on any `IntoIter` field in your
+`Diagnostic` type:
+
+```rust
+use miette::Diagnostic;
+use thiserror::Error;
+
+#[derive(Debug, Error, Diagnostic)]
+#[error("oops")]
+struct MyError {
+    #[related]
+    others: Vec<MyError>,
+}
+```
+
+### ... delayed source code
+
+Sometimes it makes sense to add source code to the error message later.
+One option is to use [`with_source_code()`](Report::with_source_code)
+method for that:
+
+```rust
+use miette::{Diagnostic, SourceSpan};
+use thiserror::Error;
+
+#[derive(Diagnostic, Debug, Error)]
+#[error("oops")]
+#[diagnostic()]
+pub struct MyErrorType {
+    // Note: label but no source code
+    #[label]
+    err_span: SourceSpan,
+}
+
+fn do_something() -> miette::Result<()> {
+    // This function emits actual error with label
+    return Err(MyErrorType {
+        err_span: (7..11).into(),
+    })?;
+}
+
+fn main() -> miette::Result<()> {
+    do_something().map_err(|error| {
+        // And this code provides the source code for inner error
+        error.with_source_code(String::from("source code"))
+    })
+}
+```
+
+Also source code can be provided by a wrapper type. This is especially
+useful in combination with `related`, when multiple errors should be
+emitted at the same time:
+
+```rust
+use miette::{Diagnostic, Report, SourceSpan};
+use thiserror::Error;
+
+#[derive(Diagnostic, Debug, Error)]
+#[error("oops")]
+#[diagnostic()]
+pub struct InnerError {
+    // Note: label but no source code
+    #[label]
+    err_span: SourceSpan,
+}
+
+#[derive(Diagnostic, Debug, Error)]
+#[error("oops: multiple errors")]
+#[diagnostic()]
+pub struct MultiError {
+    // Note source code by no labels
+    #[source_code]
+    source_code: String,
+    // The source code above is used for these errors
+    #[related]
+    related: Vec<InnerError>,
+}
+
+fn do_something() -> Result<(), Vec<InnerError>> {
+    Err(vec![
+        InnerError {
+            err_span: (0..6).into(),
+        },
+        InnerError {
+            err_span: (7..11).into(),
+        },
+    ])
+}
+
+fn main() -> miette::Result<()> {
+    do_something().map_err(|err_list| MultiError {
+        source_code: "source code".into(),
+        related: err_list,
+    })?;
+    Ok(())
+}
+```
+
+### ... Diagnostic-based error sources.
+
+When one uses the `#[source]` attribute on a field, that usually comes
+from `thiserror`, and implements a method for
+[`std::error::Error::source`]. This works in many cases, but it's lossy:
+if the source of the diagnostic is a diagnostic itself, the source will
+simply be treated as an `std::error::Error`.
+
+While this has no effect on the existing _reporters_, since they don't use
+that information right now, APIs who might want this information will have
+no access to it.
+
+If it's important for you for this information to be available to users,
+you can use `#[diagnostic_source]` alongside `#[source]`. Not that you
+will likely want to use _both_:
+
+```rust
+use miette::Diagnostic;
+use thiserror::Error;
+
+#[derive(Debug, Diagnostic, Error)]
+#[error("MyError")]
+struct MyError {
+    #[source]
+    #[diagnostic_source]
+    the_cause: OtherError,
+}
+
+#[derive(Debug, Diagnostic, Error)]
+#[error("OtherError")]
+struct OtherError;
+```
+
+### ... handler options
+
+[`MietteHandler`] is the default handler, and is very customizable. In
+most cases, you can simply use [`MietteHandlerOpts`] to tweak its behavior
+instead of falling back to your own custom handler.
+
+Usage is like so:
+
+```rust
+miette::set_hook(Box::new(|_| {
+    Box::new(
+        miette::MietteHandlerOpts::new()
+            .terminal_links(true)
+            .unicode(false)
+            .context_lines(3)
+            .tab_width(4)
+            .build(),
+    )
+}))
+```
+
+See the docs for [`MietteHandlerOpts`] for more details on what you can
+customize!
+
+### ... dynamic diagnostics
+
+If you...
+- ...don't know all the possible errors upfront
+- ...need to serialize/deserialize errors
+then you may want to use [`miette!`], [`diagnostic!`] macros or
+[`MietteDiagnostic`] directly to create diagnostic on the fly.
+
+```rust
+let source = "2 + 2 * 2 = 8".to_string();
+let report = miette!(
+  labels = vec[
+      LabeledSpan::at(12..13, "this should be 6"),
+  ],
+  help = "'*' has greater precedence than '+'",
+  "Wrong answer"
+).with_source_code(source);
+println!("{:?}", report)
+```
+
+## Acknowledgements
+
+`miette` was not developed in a void. It owes enormous credit to various
+other projects and their authors:
+
+- [`anyhow`](http://crates.io/crates/anyhow) and
+  [`color-eyre`](https://crates.io/crates/color-eyre): these two
+  enormously influential error handling libraries have pushed forward the
+  experience of application-level error handling and error reporting.
+  `miette`'s `Report` type is an attempt at a very very rough version of
+  their `Report` types.
+- [`thiserror`](https://crates.io/crates/thiserror) for setting the
+  standard for library-level error definitions, and for being the
+  inspiration behind `miette`'s derive macro.
+- `rustc` and [@estebank](https://github.com/estebank) for their
+  state-of-the-art work in compiler diagnostics.
+- [`ariadne`](https://crates.io/crates/ariadne) for pushing forward how
+  _pretty_ these diagnostics can really look!
+
+## License
+
+`miette` is released to the Rust community under the [Apache license
+2.0](./LICENSE).
+
+It also includes code taken from [`eyre`](https://github.com/yaahc/eyre),
+and some from [`thiserror`](https://github.com/dtolnay/thiserror), also
+under the Apache License. Some code is taken from
+[`ariadne`](https://github.com/zesterer/ariadne), which is MIT licensed.
+
+[`miette!`]: https://docs.rs/miette/latest/miette/macro.miette.html
+[`diagnostic!`]: https://docs.rs/miette/latest/miette/macro.diagnostic.html
+[`std::error::Error`]: https://doc.rust-lang.org/nightly/std/error/trait.Error.html
+[`Diagnostic`]: https://docs.rs/miette/latest/miette/trait.Diagnostic.html
+[`IntoDiagnostic`]: https://docs.rs/miette/latest/miette/trait.IntoDiagnostic.html
+[`MietteHandlerOpts`]: https://docs.rs/miette/latest/miette/struct.MietteHandlerOpts.html
+[`MietteHandler`]: https://docs.rs/miette/latest/miette/struct.MietteHandler.html
+[`MietteDiagnostic`]: https://docs.rs/miette/latest/miette/struct.MietteDiagnostic.html
+[`Report`]: https://docs.rs/miette/latest/miette/struct.Report.html
+[`ReportHandler`]: https://docs.rs/miette/latest/miette/struct.ReportHandler.html
+[`Result`]: https://docs.rs/miette/latest/miette/type.Result.html
+[`SourceCode`]: https://docs.rs/miette/latest/miette/struct.SourceCode.html
+[`SourceSpan`]: https://docs.rs/miette/latest/miette/struct.SourceSpan.html
diff --git a/README.tpl b/README.tpl
new file mode 100644
index 0000000..d598eb8
--- /dev/null
+++ b/README.tpl
@@ -0,0 +1,18 @@
+
+# `{{crate}}`
+
+{{readme}}
+
+[`miette!`]: https://docs.rs/miette/latest/miette/macro.miette.html
+[`diagnostic!`]: https://docs.rs/miette/latest/miette/macro.diagnostic.html
+[`std::error::Error`]: https://doc.rust-lang.org/nightly/std/error/trait.Error.html
+[`Diagnostic`]: https://docs.rs/miette/latest/miette/trait.Diagnostic.html
+[`IntoDiagnostic`]: https://docs.rs/miette/latest/miette/trait.IntoDiagnostic.html
+[`MietteHandlerOpts`]: https://docs.rs/miette/latest/miette/struct.MietteHandlerOpts.html
+[`MietteHandler`]: https://docs.rs/miette/latest/miette/struct.MietteHandler.html
+[`MietteDiagnostic`]: https://docs.rs/miette/latest/miette/struct.MietteDiagnostic.html
+[`Report`]: https://docs.rs/miette/latest/miette/struct.Report.html
+[`ReportHandler`]: https://docs.rs/miette/latest/miette/struct.ReportHandler.html
+[`Result`]: https://docs.rs/miette/latest/miette/type.Result.html
+[`SourceCode`]: https://docs.rs/miette/latest/miette/struct.SourceCode.html
+[`SourceSpan`]: https://docs.rs/miette/latest/miette/struct.SourceSpan.html
diff --git a/cliff.toml b/cliff.toml
new file mode 100644
index 0000000..22a0b78
--- /dev/null
+++ b/cliff.toml
@@ -0,0 +1,62 @@
+# configuration file for git-cliff (0.1.0)
+
+[changelog]
+# changelog header
+header = """
+# `miette` Release Changelog
+
+"""
+
+# template for the changelog body
+# https://tera.netlify.app/docs/#introduction
+body = """
+{% if version %}\
+<a name="{{ version }}"></a>
+## {{ version | replace(from="v", to="") }} ({{ timestamp | date(format="%Y-%m-%d") }})
+{% else %}\
+## Unreleased
+{% endif %}\
+{% for group, commits in commits | filter(attribute="scope") | group_by(attribute="group") %}
+### {{ group | upper_first }}
+{% for commit in commits %}
+{% if commit.scope %}\
+* **{{ commit.scope }}:** {{ commit.message }} ([{{ commit.id | truncate(length=8, end="") }}](https://github.com/zkat/miette/commit/{{ commit.id }}))
+{%- if commit.breaking %}
+    * **BREAKING CHANGE**: {{ commit.breaking_description }}
+{%- endif %}\
+{% endif %}\
+{% endfor %}
+{% endfor %}
+"""
+
+# remove the leading and trailing whitespace from the template
+trim = false
+
+# changelog footer
+# footer = """
+# <!-- generated by git-cliff -->
+# """
+
+[git]
+# allow only conventional commits
+# https://www.conventionalcommits.org
+conventional_commits = true
+# regex for parsing and grouping commits
+commit_parsers = [
+    { message = "^feat*", group = "Features"},
+    { message = "^fix*", group = "Bug Fixes"},
+    { message = "^doc*", group = "Documentation"},
+    { message = "^perf*", group = "Performance"},
+    { message = "^refactor*", group = "Refactor"},
+    { message = "^style*", group = "Styling"},
+    { message = "^test*", group = "Testing"},
+    { message = "^chore\\(release\\): prepare for*", skip = true},
+    { message = "^chore*", group = "Miscellaneous Tasks"},
+    { body = ".*security", group = "Security"},
+]
+# filter out the commits that are not matched by commit parsers
+filter_commits = true
+# glob pattern for matching git tags
+# tag_pattern = "v?[0-9]*"
+# regex for skipping tags
+# skip_tags = "v0.1.0-beta.1"
diff --git a/clippy.toml b/clippy.toml
new file mode 100644
index 0000000..0d369b5
--- /dev/null
+++ b/clippy.toml
@@ -0,0 +1 @@
+msrv = "1.56.0"
diff --git a/rustfmt.toml b/rustfmt.toml
new file mode 100644
index 0000000..8f9ebdd
--- /dev/null
+++ b/rustfmt.toml
@@ -0,0 +1,3 @@
+edition = "2021"
+wrap_comments = true
+format_code_in_doc_comments = true
diff --git a/src/chain.rs b/src/chain.rs
new file mode 100644
index 0000000..7a66383
--- /dev/null
+++ b/src/chain.rs
@@ -0,0 +1,117 @@
+/*!
+Iterate over error `.source()` chains.
+
+NOTE: This module is taken wholesale from <https://crates.io/crates/eyre>.
+*/
+use std::error::Error as StdError;
+use std::vec;
+
+use ChainState::*;
+
+/// Iterator of a chain of source errors.
+///
+/// This type is the iterator returned by [`Report::chain`].
+///
+/// # Example
+///
+/// ```
+/// use miette::Report;
+/// use std::io;
+///
+/// pub fn underlying_io_error_kind(error: &Report) -> Option<io::ErrorKind> {
+///     for cause in error.chain() {
+///         if let Some(io_error) = cause.downcast_ref::<io::Error>() {
+///             return Some(io_error.kind());
+///         }
+///     }
+///     None
+/// }
+/// ```
+#[derive(Clone)]
+#[allow(missing_debug_implementations)]
+pub struct Chain<'a> {
+    state: crate::chain::ChainState<'a>,
+}
+
+#[derive(Clone)]
+pub(crate) enum ChainState<'a> {
+    Linked {
+        next: Option<&'a (dyn StdError + 'static)>,
+    },
+    Buffered {
+        rest: vec::IntoIter<&'a (dyn StdError + 'static)>,
+    },
+}
+
+impl<'a> Chain<'a> {
+    pub(crate) fn new(head: &'a (dyn StdError + 'static)) -> Self {
+        Chain {
+            state: ChainState::Linked { next: Some(head) },
+        }
+    }
+}
+
+impl<'a> Iterator for Chain<'a> {
+    type Item = &'a (dyn StdError + 'static);
+
+    fn next(&mut self) -> Option<Self::Item> {
+        match &mut self.state {
+            Linked { next } => {
+                let error = (*next)?;
+                *next = error.source();
+                Some(error)
+            }
+            Buffered { rest } => rest.next(),
+        }
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        let len = self.len();
+        (len, Some(len))
+    }
+}
+
+impl DoubleEndedIterator for Chain<'_> {
+    fn next_back(&mut self) -> Option<Self::Item> {
+        match &mut self.state {
+            Linked { mut next } => {
+                let mut rest = Vec::new();
+                while let Some(cause) = next {
+                    next = cause.source();
+                    rest.push(cause);
+                }
+                let mut rest = rest.into_iter();
+                let last = rest.next_back();
+                self.state = Buffered { rest };
+                last
+            }
+            Buffered { rest } => rest.next_back(),
+        }
+    }
+}
+
+impl ExactSizeIterator for Chain<'_> {
+    fn len(&self) -> usize {
+        match &self.state {
+            Linked { mut next } => {
+                let mut len = 0;
+                while let Some(cause) = next {
+                    next = cause.source();
+                    len += 1;
+                }
+                len
+            }
+            Buffered { rest } => rest.len(),
+        }
+    }
+}
+
+impl Default for Chain<'_> {
+    fn default() -> Self {
+        Chain {
+            state: ChainState::Buffered {
+                rest: Vec::new().into_iter(),
+            },
+        }
+    }
+}
diff --git a/src/diagnostic_chain.rs b/src/diagnostic_chain.rs
new file mode 100644
index 0000000..1e5e0c2
--- /dev/null
+++ b/src/diagnostic_chain.rs
@@ -0,0 +1,93 @@
+/*!
+Iterate over error `.diagnostic_source()` chains.
+*/
+
+use crate::protocol::Diagnostic;
+
+/// Iterator of a chain of cause errors.
+#[derive(Clone, Default)]
+#[allow(missing_debug_implementations)]
+pub(crate) struct DiagnosticChain<'a> {
+    state: Option<ErrorKind<'a>>,
+}
+
+impl<'a> DiagnosticChain<'a> {
+    pub(crate) fn from_diagnostic(head: &'a dyn Diagnostic) -> Self {
+        DiagnosticChain {
+            state: Some(ErrorKind::Diagnostic(head)),
+        }
+    }
+
+    pub(crate) fn from_stderror(head: &'a (dyn std::error::Error + 'static)) -> Self {
+        DiagnosticChain {
+            state: Some(ErrorKind::StdError(head)),
+        }
+    }
+}
+
+impl<'a> Iterator for DiagnosticChain<'a> {
+    type Item = ErrorKind<'a>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        if let Some(err) = self.state.take() {
+            self.state = err.get_nested();
+            Some(err)
+        } else {
+            None
+        }
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        let len = self.len();
+        (len, Some(len))
+    }
+}
+
+impl ExactSizeIterator for DiagnosticChain<'_> {
+    fn len(&self) -> usize {
+        fn depth(d: Option<&ErrorKind<'_>>) -> usize {
+            match d {
+                Some(d) => 1 + depth(d.get_nested().as_ref()),
+                None => 0,
+            }
+        }
+
+        depth(self.state.as_ref())
+    }
+}
+
+#[derive(Clone)]
+pub(crate) enum ErrorKind<'a> {
+    Diagnostic(&'a dyn Diagnostic),
+    StdError(&'a (dyn std::error::Error + 'static)),
+}
+
+impl<'a> ErrorKind<'a> {
+    fn get_nested(&self) -> Option<ErrorKind<'a>> {
+        match self {
+            ErrorKind::Diagnostic(d) => d
+                .diagnostic_source()
+                .map(ErrorKind::Diagnostic)
+                .or_else(|| d.source().map(ErrorKind::StdError)),
+            ErrorKind::StdError(e) => e.source().map(ErrorKind::StdError),
+        }
+    }
+}
+
+impl<'a> std::fmt::Debug for ErrorKind<'a> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            ErrorKind::Diagnostic(d) => d.fmt(f),
+            ErrorKind::StdError(e) => e.fmt(f),
+        }
+    }
+}
+
+impl<'a> std::fmt::Display for ErrorKind<'a> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            ErrorKind::Diagnostic(d) => d.fmt(f),
+            ErrorKind::StdError(e) => e.fmt(f),
+        }
+    }
+}
diff --git a/src/error.rs b/src/error.rs
new file mode 100644
index 0000000..56041ca
--- /dev/null
+++ b/src/error.rs
@@ -0,0 +1,27 @@
+use std::io;
+
+use thiserror::Error;
+
+use crate::{self as miette, Diagnostic};
+
+/**
+Error enum for miette. Used by certain operations in the protocol.
+*/
+#[derive(Debug, Diagnostic, Error)]
+pub enum MietteError {
+    /// Wrapper around [`std::io::Error`]. This is returned when something went
+    /// wrong while reading a [`SourceCode`](crate::SourceCode).
+    #[error(transparent)]
+    #[diagnostic(code(miette::io_error), url(docsrs))]
+    IoError(#[from] io::Error),
+
+    /// Returned when a [`SourceSpan`](crate::SourceSpan) extends beyond the
+    /// bounds of a given [`SourceCode`](crate::SourceCode).
+    #[error("The given offset is outside the bounds of its Source")]
+    #[diagnostic(
+        code(miette::span_out_of_bounds),
+        help("Double-check your spans. Do you have an off-by-one error?"),
+        url(docsrs)
+    )]
+    OutOfBounds,
+}
diff --git a/src/eyreish/context.rs b/src/eyreish/context.rs
new file mode 100644
index 0000000..3d9238b
--- /dev/null
+++ b/src/eyreish/context.rs
@@ -0,0 +1,217 @@
+use super::error::{ContextError, ErrorImpl};
+use super::{Report, WrapErr};
+use core::fmt::{self, Debug, Display, Write};
+
+use std::error::Error as StdError;
+
+use crate::{Diagnostic, LabeledSpan};
+
+mod ext {
+    use super::*;
+
+    pub trait Diag {
+        #[cfg_attr(track_caller, track_caller)]
+        fn ext_report<D>(self, msg: D) -> Report
+        where
+            D: Display + Send + Sync + 'static;
+    }
+
+    impl<E> Diag for E
+    where
+        E: Diagnostic + Send + Sync + 'static,
+    {
+        fn ext_report<D>(self, msg: D) -> Report
+        where
+            D: Display + Send + Sync + 'static,
+        {
+            Report::from_msg(msg, self)
+        }
+    }
+
+    impl Diag for Report {
+        fn ext_report<D>(self, msg: D) -> Report
+        where
+            D: Display + Send + Sync + 'static,
+        {
+            self.wrap_err(msg)
+        }
+    }
+}
+
+impl<T, E> WrapErr<T, E> for Result<T, E>
+where
+    E: ext::Diag + Send + Sync + 'static,
+{
+    fn wrap_err<D>(self, msg: D) -> Result<T, Report>
+    where
+        D: Display + Send + Sync + 'static,
+    {
+        match self {
+            Ok(t) => Ok(t),
+            Err(e) => Err(e.ext_report(msg)),
+        }
+    }
+
+    fn wrap_err_with<D, F>(self, msg: F) -> Result<T, Report>
+    where
+        D: Display + Send + Sync + 'static,
+        F: FnOnce() -> D,
+    {
+        match self {
+            Ok(t) => Ok(t),
+            Err(e) => Err(e.ext_report(msg())),
+        }
+    }
+
+    fn context<D>(self, msg: D) -> Result<T, Report>
+    where
+        D: Display + Send + Sync + 'static,
+    {
+        self.wrap_err(msg)
+    }
+
+    fn with_context<D, F>(self, msg: F) -> Result<T, Report>
+    where
+        D: Display + Send + Sync + 'static,
+        F: FnOnce() -> D,
+    {
+        self.wrap_err_with(msg)
+    }
+}
+
+impl<D, E> Debug for ContextError<D, E>
+where
+    D: Display,
+    E: Debug,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("Error")
+            .field("msg", &Quoted(&self.msg))
+            .field("source", &self.error)
+            .finish()
+    }
+}
+
+impl<D, E> Display for ContextError<D, E>
+where
+    D: Display,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        Display::fmt(&self.msg, f)
+    }
+}
+
+impl<D, E> StdError for ContextError<D, E>
+where
+    D: Display,
+    E: StdError + 'static,
+{
+    fn source(&self) -> Option<&(dyn StdError + 'static)> {
+        Some(&self.error)
+    }
+}
+
+impl<D> StdError for ContextError<D, Report>
+where
+    D: Display,
+{
+    fn source(&self) -> Option<&(dyn StdError + 'static)> {
+        unsafe { Some(ErrorImpl::error(self.error.inner.by_ref())) }
+    }
+}
+
+impl<D, E> Diagnostic for ContextError<D, E>
+where
+    D: Display,
+    E: Diagnostic + 'static,
+{
+    fn code<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        self.error.code()
+    }
+
+    fn severity(&self) -> Option<crate::Severity> {
+        self.error.severity()
+    }
+
+    fn help<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        self.error.help()
+    }
+
+    fn url<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        self.error.url()
+    }
+
+    fn labels<'a>(&'a self) -> Option<Box<dyn Iterator<Item = LabeledSpan> + 'a>> {
+        self.error.labels()
+    }
+
+    fn source_code(&self) -> Option<&dyn crate::SourceCode> {
+        self.error.source_code()
+    }
+
+    fn related<'a>(&'a self) -> Option<Box<dyn Iterator<Item = &'a dyn Diagnostic> + 'a>> {
+        self.error.related()
+    }
+}
+
+impl<D> Diagnostic for ContextError<D, Report>
+where
+    D: Display,
+{
+    fn code<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        unsafe { ErrorImpl::diagnostic(self.error.inner.by_ref()).code() }
+    }
+
+    fn severity(&self) -> Option<crate::Severity> {
+        unsafe { ErrorImpl::diagnostic(self.error.inner.by_ref()).severity() }
+    }
+
+    fn help<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        unsafe { ErrorImpl::diagnostic(self.error.inner.by_ref()).help() }
+    }
+
+    fn url<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        unsafe { ErrorImpl::diagnostic(self.error.inner.by_ref()).url() }
+    }
+
+    fn labels<'a>(&'a self) -> Option<Box<dyn Iterator<Item = LabeledSpan> + 'a>> {
+        unsafe { ErrorImpl::diagnostic(self.error.inner.by_ref()).labels() }
+    }
+
+    fn source_code(&self) -> Option<&dyn crate::SourceCode> {
+        self.error.source_code()
+    }
+
+    fn related<'a>(&'a self) -> Option<Box<dyn Iterator<Item = &'a dyn Diagnostic> + 'a>> {
+        self.error.related()
+    }
+}
+
+struct Quoted<D>(D);
+
+impl<D> Debug for Quoted<D>
+where
+    D: Display,
+{
+    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
+        formatter.write_char('"')?;
+        Quoted(&mut *formatter).write_fmt(format_args!("{}", self.0))?;
+        formatter.write_char('"')?;
+        Ok(())
+    }
+}
+
+impl Write for Quoted<&mut fmt::Formatter<'_>> {
+    fn write_str(&mut self, s: &str) -> fmt::Result {
+        Display::fmt(&s.escape_debug(), self.0)
+    }
+}
+
+pub(crate) mod private {
+    use super::*;
+
+    pub trait Sealed {}
+
+    impl<T, E> Sealed for Result<T, E> where E: ext::Diag {}
+    impl<T> Sealed for Option<T> {}
+}
diff --git a/src/eyreish/error.rs b/src/eyreish/error.rs
new file mode 100644
index 0000000..6b0dc34
--- /dev/null
+++ b/src/eyreish/error.rs
@@ -0,0 +1,810 @@
+use core::any::TypeId;
+use core::fmt::{self, Debug, Display};
+use core::mem::ManuallyDrop;
+use core::ptr::{self, NonNull};
+use std::error::Error as StdError;
+
+use super::ptr::{Mut, Own, Ref};
+use super::Report;
+use super::ReportHandler;
+use crate::chain::Chain;
+use crate::eyreish::wrapper::WithSourceCode;
+use crate::{Diagnostic, SourceCode};
+use core::ops::{Deref, DerefMut};
+
+impl Report {
+    /// Create a new error object from any error type.
+    ///
+    /// The error type must be thread safe and `'static`, so that the `Report`
+    /// will be as well.
+    ///
+    /// If the error type does not provide a backtrace, a backtrace will be
+    /// created here to ensure that a backtrace exists.
+    #[cfg_attr(track_caller, track_caller)]
+    pub fn new<E>(error: E) -> Self
+    where
+        E: Diagnostic + Send + Sync + 'static,
+    {
+        Report::from_std(error)
+    }
+
+    /// Create a new error object from a printable error message.
+    ///
+    /// If the argument implements std::error::Error, prefer `Report::new`
+    /// instead which preserves the underlying error's cause chain and
+    /// backtrace. If the argument may or may not implement std::error::Error
+    /// now or in the future, use `miette!(err)` which handles either way
+    /// correctly.
+    ///
+    /// `Report::msg("...")` is equivalent to `miette!("...")` but occasionally
+    /// convenient in places where a function is preferable over a macro, such
+    /// as iterator or stream combinators:
+    ///
+    /// ```
+    /// # mod ffi {
+    /// #     pub struct Input;
+    /// #     pub struct Output;
+    /// #     pub async fn do_some_work(_: Input) -> Result<Output, &'static str> {
+    /// #         unimplemented!()
+    /// #     }
+    /// # }
+    /// #
+    /// # use ffi::{Input, Output};
+    /// #
+    /// use futures::stream::{Stream, StreamExt, TryStreamExt};
+    /// use miette::{Report, Result};
+    ///
+    /// async fn demo<S>(stream: S) -> Result<Vec<Output>>
+    /// where
+    ///     S: Stream<Item = Input>,
+    /// {
+    ///     stream
+    ///         .then(ffi::do_some_work) // returns Result<Output, &str>
+    ///         .map_err(Report::msg)
+    ///         .try_collect()
+    ///         .await
+    /// }
+    /// ```
+    #[cfg_attr(track_caller, track_caller)]
+    pub fn msg<M>(message: M) -> Self
+    where
+        M: Display + Debug + Send + Sync + 'static,
+    {
+        Report::from_adhoc(message)
+    }
+
+    /// Create a new error object from a boxed [`Diagnostic`].
+    ///
+    /// The boxed type must be thread safe and 'static, so that the `Report`
+    /// will be as well.
+    ///
+    /// Boxed `Diagnostic`s don't implement `Diagnostic` themselves due to trait coherence issues.
+    /// This method allows you to create a `Report` from a boxed `Diagnostic`.
+    #[cfg_attr(track_caller, track_caller)]
+    pub fn new_boxed(error: Box<dyn Diagnostic + Send + Sync + 'static>) -> Self {
+        Report::from_boxed(error)
+    }
+
+    #[cfg_attr(track_caller, track_caller)]
+    pub(crate) fn from_std<E>(error: E) -> Self
+    where
+        E: Diagnostic + Send + Sync + 'static,
+    {
+        let vtable = &ErrorVTable {
+            object_drop: object_drop::<E>,
+            object_ref: object_ref::<E>,
+            object_ref_stderr: object_ref_stderr::<E>,
+            object_boxed: object_boxed::<E>,
+            object_boxed_stderr: object_boxed_stderr::<E>,
+            object_downcast: object_downcast::<E>,
+            object_drop_rest: object_drop_front::<E>,
+        };
+
+        // Safety: passing vtable that operates on the right type E.
+        let handler = Some(super::capture_handler(&error));
+
+        unsafe { Report::construct(error, vtable, handler) }
+    }
+
+    #[cfg_attr(track_caller, track_caller)]
+    pub(crate) fn from_adhoc<M>(message: M) -> Self
+    where
+        M: Display + Debug + Send + Sync + 'static,
+    {
+        use super::wrapper::MessageError;
+        let error: MessageError<M> = MessageError(message);
+        let vtable = &ErrorVTable {
+            object_drop: object_drop::<MessageError<M>>,
+            object_ref: object_ref::<MessageError<M>>,
+            object_ref_stderr: object_ref_stderr::<MessageError<M>>,
+            object_boxed: object_boxed::<MessageError<M>>,
+            object_boxed_stderr: object_boxed_stderr::<MessageError<M>>,
+            object_downcast: object_downcast::<M>,
+            object_drop_rest: object_drop_front::<M>,
+        };
+
+        // Safety: MessageError is repr(transparent) so it is okay for the
+        // vtable to allow casting the MessageError<M> to M.
+        let handler = Some(super::capture_handler(&error));
+
+        unsafe { Report::construct(error, vtable, handler) }
+    }
+
+    #[cfg_attr(track_caller, track_caller)]
+    pub(crate) fn from_msg<D, E>(msg: D, error: E) -> Self
+    where
+        D: Display + Send + Sync + 'static,
+        E: Diagnostic + Send + Sync + 'static,
+    {
+        let error: ContextError<D, E> = ContextError { msg, error };
+
+        let vtable = &ErrorVTable {
+            object_drop: object_drop::<ContextError<D, E>>,
+            object_ref: object_ref::<ContextError<D, E>>,
+            object_ref_stderr: object_ref_stderr::<ContextError<D, E>>,
+            object_boxed: object_boxed::<ContextError<D, E>>,
+            object_boxed_stderr: object_boxed_stderr::<ContextError<D, E>>,
+            object_downcast: context_downcast::<D, E>,
+            object_drop_rest: context_drop_rest::<D, E>,
+        };
+
+        // Safety: passing vtable that operates on the right type.
+        let handler = Some(super::capture_handler(&error));
+
+        unsafe { Report::construct(error, vtable, handler) }
+    }
+
+    #[cfg_attr(track_caller, track_caller)]
+    pub(crate) fn from_boxed(error: Box<dyn Diagnostic + Send + Sync>) -> Self {
+        use super::wrapper::BoxedError;
+        let error = BoxedError(error);
+        let handler = Some(super::capture_handler(&error));
+
+        let vtable = &ErrorVTable {
+            object_drop: object_drop::<BoxedError>,
+            object_ref: object_ref::<BoxedError>,
+            object_ref_stderr: object_ref_stderr::<BoxedError>,
+            object_boxed: object_boxed::<BoxedError>,
+            object_boxed_stderr: object_boxed_stderr::<BoxedError>,
+            object_downcast: object_downcast::<Box<dyn Diagnostic + Send + Sync>>,
+            object_drop_rest: object_drop_front::<Box<dyn Diagnostic + Send + Sync>>,
+        };
+
+        // Safety: BoxedError is repr(transparent) so it is okay for the vtable
+        // to allow casting to Box<dyn StdError + Send + Sync>.
+        unsafe { Report::construct(error, vtable, handler) }
+    }
+
+    // Takes backtrace as argument rather than capturing it here so that the
+    // user sees one fewer layer of wrapping noise in the backtrace.
+    //
+    // Unsafe because the given vtable must have sensible behavior on the error
+    // value of type E.
+    unsafe fn construct<E>(
+        error: E,
+        vtable: &'static ErrorVTable,
+        handler: Option<Box<dyn ReportHandler>>,
+    ) -> Self
+    where
+        E: Diagnostic + Send + Sync + 'static,
+    {
+        let inner = Box::new(ErrorImpl {
+            vtable,
+            handler,
+            _object: error,
+        });
+        // Erase the concrete type of E from the compile-time type system. This
+        // is equivalent to the safe unsize coercion from Box<ErrorImpl<E>> to
+        // Box<ErrorImpl<dyn StdError + Send + Sync + 'static>> except that the
+        // result is a thin pointer. The necessary behavior for manipulating the
+        // underlying ErrorImpl<E> is preserved in the vtable provided by the
+        // caller rather than a builtin fat pointer vtable.
+        let inner = Own::new(inner).cast::<ErasedErrorImpl>();
+        Report { inner }
+    }
+
+    /// Create a new error from an error message to wrap the existing error.
+    ///
+    /// For attaching a higher level error message to a `Result` as it is
+    /// propagated, the [crate::WrapErr] extension trait may be more
+    /// convenient than this function.
+    ///
+    /// The primary reason to use `error.wrap_err(...)` instead of
+    /// `result.wrap_err(...)` via the `WrapErr` trait would be if the
+    /// message needs to depend on some data held by the underlying error:
+    pub fn wrap_err<D>(self, msg: D) -> Self
+    where
+        D: Display + Send + Sync + 'static,
+    {
+        let handler = unsafe { self.inner.by_mut().deref_mut().handler.take() };
+        let error: ContextError<D, Report> = ContextError { msg, error: self };
+
+        let vtable = &ErrorVTable {
+            object_drop: object_drop::<ContextError<D, Report>>,
+            object_ref: object_ref::<ContextError<D, Report>>,
+            object_ref_stderr: object_ref_stderr::<ContextError<D, Report>>,
+            object_boxed: object_boxed::<ContextError<D, Report>>,
+            object_boxed_stderr: object_boxed_stderr::<ContextError<D, Report>>,
+            object_downcast: context_chain_downcast::<D>,
+            object_drop_rest: context_chain_drop_rest::<D>,
+        };
+
+        // Safety: passing vtable that operates on the right type.
+        unsafe { Report::construct(error, vtable, handler) }
+    }
+
+    /// Compatibility re-export of wrap_err for interop with `anyhow`
+    pub fn context<D>(self, msg: D) -> Self
+    where
+        D: Display + Send + Sync + 'static,
+    {
+        self.wrap_err(msg)
+    }
+
+    /// An iterator of the chain of source errors contained by this Report.
+    ///
+    /// This iterator will visit every error in the cause chain of this error
+    /// object, beginning with the error that this error object was created
+    /// from.
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// use miette::Report;
+    /// use std::io;
+    ///
+    /// pub fn underlying_io_error_kind(error: &Report) -> Option<io::ErrorKind> {
+    ///     for cause in error.chain() {
+    ///         if let Some(io_error) = cause.downcast_ref::<io::Error>() {
+    ///             return Some(io_error.kind());
+    ///         }
+    ///     }
+    ///     None
+    /// }
+    /// ```
+    pub fn chain(&self) -> Chain<'_> {
+        unsafe { ErrorImpl::chain(self.inner.by_ref()) }
+    }
+
+    /// The lowest level cause of this error &mdash; this error's cause's
+    /// cause's cause etc.
+    ///
+    /// The root cause is the last error in the iterator produced by
+    /// [`chain()`](Report::chain).
+    pub fn root_cause(&self) -> &(dyn StdError + 'static) {
+        self.chain().last().unwrap()
+    }
+
+    /// Returns true if `E` is the type held by this error object.
+    ///
+    /// For errors constructed from messages, this method returns true if `E`
+    /// matches the type of the message `D` **or** the type of the error on
+    /// which the message has been attached. For details about the
+    /// interaction between message and downcasting, [see here].
+    ///
+    /// [see here]: trait.WrapErr.html#effect-on-downcasting
+    pub fn is<E>(&self) -> bool
+    where
+        E: Display + Debug + Send + Sync + 'static,
+    {
+        self.downcast_ref::<E>().is_some()
+    }
+
+    /// Attempt to downcast the error object to a concrete type.
+    pub fn downcast<E>(self) -> Result<E, Self>
+    where
+        E: Display + Debug + Send + Sync + 'static,
+    {
+        let target = TypeId::of::<E>();
+        let inner = self.inner.by_mut();
+        unsafe {
+            // Use vtable to find NonNull<()> which points to a value of type E
+            // somewhere inside the data structure.
+            let addr = match (vtable(inner.ptr).object_downcast)(inner.by_ref(), target) {
+                Some(addr) => addr.by_mut().extend(),
+                None => return Err(self),
+            };
+
+            // Prepare to read E out of the data structure. We'll drop the rest
+            // of the data structure separately so that E is not dropped.
+            let outer = ManuallyDrop::new(self);
+
+            // Read E from where the vtable found it.
+            let error = addr.cast::<E>().read();
+
+            // Drop rest of the data structure outside of E.
+            (vtable(outer.inner.ptr).object_drop_rest)(outer.inner, target);
+
+            Ok(error)
+        }
+    }
+
+    /// Downcast this error object by reference.
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// # use miette::{Report, miette};
+    /// # use std::fmt::{self, Display};
+    /// # use std::task::Poll;
+    /// #
+    /// # #[derive(Debug)]
+    /// # enum DataStoreError {
+    /// #     Censored(()),
+    /// # }
+    /// #
+    /// # impl Display for DataStoreError {
+    /// #     fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
+    /// #         unimplemented!()
+    /// #     }
+    /// # }
+    /// #
+    /// # impl std::error::Error for DataStoreError {}
+    /// #
+    /// # const REDACTED_CONTENT: () = ();
+    /// #
+    /// # let error: Report = miette!("...");
+    /// # let root_cause = &error;
+    /// #
+    /// # let ret =
+    /// // If the error was caused by redaction, then return a tombstone instead
+    /// // of the content.
+    /// match root_cause.downcast_ref::<DataStoreError>() {
+    ///     Some(DataStoreError::Censored(_)) => Ok(Poll::Ready(REDACTED_CONTENT)),
+    ///     None => Err(error),
+    /// }
+    /// # ;
+    /// ```
+    pub fn downcast_ref<E>(&self) -> Option<&E>
+    where
+        E: Display + Debug + Send + Sync + 'static,
+    {
+        let target = TypeId::of::<E>();
+        unsafe {
+            // Use vtable to find NonNull<()> which points to a value of type E
+            // somewhere inside the data structure.
+            let addr = (vtable(self.inner.ptr).object_downcast)(self.inner.by_ref(), target)?;
+            Some(addr.cast::<E>().deref())
+        }
+    }
+
+    /// Downcast this error object by mutable reference.
+    pub fn downcast_mut<E>(&mut self) -> Option<&mut E>
+    where
+        E: Display + Debug + Send + Sync + 'static,
+    {
+        let target = TypeId::of::<E>();
+        unsafe {
+            // Use vtable to find NonNull<()> which points to a value of type E
+            // somewhere inside the data structure.
+            let addr =
+                (vtable(self.inner.ptr).object_downcast)(self.inner.by_ref(), target)?.by_mut();
+            Some(addr.cast::<E>().deref_mut())
+        }
+    }
+
+    /// Get a reference to the Handler for this Report.
+    pub fn handler(&self) -> &dyn ReportHandler {
+        unsafe {
+            self.inner
+                .by_ref()
+                .deref()
+                .handler
+                .as_ref()
+                .unwrap()
+                .as_ref()
+        }
+    }
+
+    /// Get a mutable reference to the Handler for this Report.
+    pub fn handler_mut(&mut self) -> &mut dyn ReportHandler {
+        unsafe {
+            self.inner
+                .by_mut()
+                .deref_mut()
+                .handler
+                .as_mut()
+                .unwrap()
+                .as_mut()
+        }
+    }
+
+    /// Provide source code for this error
+    pub fn with_source_code(self, source_code: impl SourceCode + Send + Sync + 'static) -> Report {
+        WithSourceCode {
+            source_code,
+            error: self,
+        }
+        .into()
+    }
+}
+
+impl<E> From<E> for Report
+where
+    E: Diagnostic + Send + Sync + 'static,
+{
+    #[cfg_attr(track_caller, track_caller)]
+    fn from(error: E) -> Self {
+        Report::from_std(error)
+    }
+}
+
+impl Deref for Report {
+    type Target = dyn Diagnostic + Send + Sync + 'static;
+
+    fn deref(&self) -> &Self::Target {
+        unsafe { ErrorImpl::diagnostic(self.inner.by_ref()) }
+    }
+}
+
+impl DerefMut for Report {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        unsafe { ErrorImpl::diagnostic_mut(self.inner.by_mut()) }
+    }
+}
+
+impl Display for Report {
+    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
+        unsafe { ErrorImpl::display(self.inner.by_ref(), formatter) }
+    }
+}
+
+impl Debug for Report {
+    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
+        unsafe { ErrorImpl::debug(self.inner.by_ref(), formatter) }
+    }
+}
+
+impl Drop for Report {
+    fn drop(&mut self) {
+        unsafe {
+            // Invoke the vtable's drop behavior.
+            (vtable(self.inner.ptr).object_drop)(self.inner);
+        }
+    }
+}
+
+struct ErrorVTable {
+    object_drop: unsafe fn(Own<ErasedErrorImpl>),
+    object_ref:
+        unsafe fn(Ref<'_, ErasedErrorImpl>) -> Ref<'_, dyn Diagnostic + Send + Sync + 'static>,
+    object_ref_stderr:
+        unsafe fn(Ref<'_, ErasedErrorImpl>) -> Ref<'_, dyn StdError + Send + Sync + 'static>,
+    #[allow(clippy::type_complexity)]
+    object_boxed: unsafe fn(Own<ErasedErrorImpl>) -> Box<dyn Diagnostic + Send + Sync + 'static>,
+    #[allow(clippy::type_complexity)]
+    object_boxed_stderr:
+        unsafe fn(Own<ErasedErrorImpl>) -> Box<dyn StdError + Send + Sync + 'static>,
+    object_downcast: unsafe fn(Ref<'_, ErasedErrorImpl>, TypeId) -> Option<Ref<'_, ()>>,
+    object_drop_rest: unsafe fn(Own<ErasedErrorImpl>, TypeId),
+}
+
+// Safety: requires layout of *e to match ErrorImpl<E>.
+unsafe fn object_drop<E>(e: Own<ErasedErrorImpl>) {
+    // Cast back to ErrorImpl<E> so that the allocator receives the correct
+    // Layout to deallocate the Box's memory.
+    let unerased = e.cast::<ErrorImpl<E>>().boxed();
+    drop(unerased);
+}
+
+// Safety: requires layout of *e to match ErrorImpl<E>.
+unsafe fn object_drop_front<E>(e: Own<ErasedErrorImpl>, target: TypeId) {
+    // Drop the fields of ErrorImpl other than E as well as the Box allocation,
+    // without dropping E itself. This is used by downcast after doing a
+    // ptr::read to take ownership of the E.
+    let _ = target;
+    let unerased = e.cast::<ErrorImpl<ManuallyDrop<E>>>().boxed();
+    drop(unerased);
+}
+
+// Safety: requires layout of *e to match ErrorImpl<E>.
+unsafe fn object_ref<E>(
+    e: Ref<'_, ErasedErrorImpl>,
+) -> Ref<'_, dyn Diagnostic + Send + Sync + 'static>
+where
+    E: Diagnostic + Send + Sync + 'static,
+{
+    // Attach E's native StdError vtable onto a pointer to self._object.
+    let unerased = e.cast::<ErrorImpl<E>>();
+
+    Ref::from_raw(NonNull::new_unchecked(
+        ptr::addr_of!((*unerased.as_ptr())._object) as *mut E,
+    ))
+}
+
+// Safety: requires layout of *e to match ErrorImpl<E>.
+unsafe fn object_ref_stderr<E>(
+    e: Ref<'_, ErasedErrorImpl>,
+) -> Ref<'_, dyn StdError + Send + Sync + 'static>
+where
+    E: StdError + Send + Sync + 'static,
+{
+    // Attach E's native StdError vtable onto a pointer to self._object.
+    let unerased = e.cast::<ErrorImpl<E>>();
+
+    Ref::from_raw(NonNull::new_unchecked(
+        ptr::addr_of!((*unerased.as_ptr())._object) as *mut E,
+    ))
+}
+
+// Safety: requires layout of *e to match ErrorImpl<E>.
+unsafe fn object_boxed<E>(e: Own<ErasedErrorImpl>) -> Box<dyn Diagnostic + Send + Sync + 'static>
+where
+    E: Diagnostic + Send + Sync + 'static,
+{
+    // Attach ErrorImpl<E>'s native StdError vtable. The StdError impl is below.
+    e.cast::<ErrorImpl<E>>().boxed()
+}
+
+// Safety: requires layout of *e to match ErrorImpl<E>.
+unsafe fn object_boxed_stderr<E>(
+    e: Own<ErasedErrorImpl>,
+) -> Box<dyn StdError + Send + Sync + 'static>
+where
+    E: StdError + Send + Sync + 'static,
+{
+    // Attach ErrorImpl<E>'s native StdError vtable. The StdError impl is below.
+    e.cast::<ErrorImpl<E>>().boxed()
+}
+
+// Safety: requires layout of *e to match ErrorImpl<E>.
+unsafe fn object_downcast<E>(e: Ref<'_, ErasedErrorImpl>, target: TypeId) -> Option<Ref<'_, ()>>
+where
+    E: 'static,
+{
+    if TypeId::of::<E>() == target {
+        // Caller is looking for an E pointer and e is ErrorImpl<E>, take a
+        // pointer to its E field.
+        let unerased = e.cast::<ErrorImpl<E>>();
+
+        Some(
+            Ref::from_raw(NonNull::new_unchecked(
+                ptr::addr_of!((*unerased.as_ptr())._object) as *mut E,
+            ))
+            .cast::<()>(),
+        )
+    } else {
+        None
+    }
+}
+
+// Safety: requires layout of *e to match ErrorImpl<ContextError<D, E>>.
+unsafe fn context_downcast<D, E>(e: Ref<'_, ErasedErrorImpl>, target: TypeId) -> Option<Ref<'_, ()>>
+where
+    D: 'static,
+    E: 'static,
+{
+    if TypeId::of::<D>() == target {
+        let unerased = e.cast::<ErrorImpl<ContextError<D, E>>>().deref();
+        Some(Ref::new(&unerased._object.msg).cast::<()>())
+    } else if TypeId::of::<E>() == target {
+        let unerased = e.cast::<ErrorImpl<ContextError<D, E>>>().deref();
+        Some(Ref::new(&unerased._object.error).cast::<()>())
+    } else {
+        None
+    }
+}
+
+// Safety: requires layout of *e to match ErrorImpl<ContextError<D, E>>.
+unsafe fn context_drop_rest<D, E>(e: Own<ErasedErrorImpl>, target: TypeId)
+where
+    D: 'static,
+    E: 'static,
+{
+    // Called after downcasting by value to either the D or the E and doing a
+    // ptr::read to take ownership of that value.
+    if TypeId::of::<D>() == target {
+        let unerased = e
+            .cast::<ErrorImpl<ContextError<ManuallyDrop<D>, E>>>()
+            .boxed();
+        drop(unerased);
+    } else {
+        let unerased = e
+            .cast::<ErrorImpl<ContextError<D, ManuallyDrop<E>>>>()
+            .boxed();
+        drop(unerased);
+    }
+}
+
+// Safety: requires layout of *e to match ErrorImpl<ContextError<D, Report>>.
+unsafe fn context_chain_downcast<D>(
+    e: Ref<'_, ErasedErrorImpl>,
+    target: TypeId,
+) -> Option<Ref<'_, ()>>
+where
+    D: 'static,
+{
+    let unerased = e.cast::<ErrorImpl<ContextError<D, Report>>>().deref();
+    if TypeId::of::<D>() == target {
+        Some(Ref::new(&unerased._object.msg).cast::<()>())
+    } else {
+        // Recurse down the context chain per the inner error's vtable.
+        let source = &unerased._object.error;
+        (vtable(source.inner.ptr).object_downcast)(source.inner.by_ref(), target)
+    }
+}
+
+// Safety: requires layout of *e to match ErrorImpl<ContextError<D, Report>>.
+unsafe fn context_chain_drop_rest<D>(e: Own<ErasedErrorImpl>, target: TypeId)
+where
+    D: 'static,
+{
+    // Called after downcasting by value to either the D or one of the causes
+    // and doing a ptr::read to take ownership of that value.
+    if TypeId::of::<D>() == target {
+        let unerased = e
+            .cast::<ErrorImpl<ContextError<ManuallyDrop<D>, Report>>>()
+            .boxed();
+        // Drop the entire rest of the data structure rooted in the next Report.
+        drop(unerased);
+    } else {
+        let unerased = e
+            .cast::<ErrorImpl<ContextError<D, ManuallyDrop<Report>>>>()
+            .boxed();
+        // Read out a ManuallyDrop<Box<ErasedErrorImpl>> from the next error.
+        let inner = unerased._object.error.inner;
+        drop(unerased);
+        let vtable = vtable(inner.ptr);
+        // Recursively drop the next error using the same target typeid.
+        (vtable.object_drop_rest)(inner, target);
+    }
+}
+
+// repr C to ensure that E remains in the final position.
+#[repr(C)]
+pub(crate) struct ErrorImpl<E> {
+    vtable: &'static ErrorVTable,
+    pub(crate) handler: Option<Box<dyn ReportHandler>>,
+    // NOTE: Don't use directly. Use only through vtable. Erased type may have
+    // different alignment.
+    _object: E,
+}
+
+// repr C to ensure that ContextError<D, E> has the same layout as
+// ContextError<ManuallyDrop<D>, E> and ContextError<D, ManuallyDrop<E>>.
+#[repr(C)]
+pub(crate) struct ContextError<D, E> {
+    pub(crate) msg: D,
+    pub(crate) error: E,
+}
+
+type ErasedErrorImpl = ErrorImpl<()>;
+
+// Safety: `ErrorVTable` must be the first field of `ErrorImpl`
+unsafe fn vtable(p: NonNull<ErasedErrorImpl>) -> &'static ErrorVTable {
+    (p.as_ptr() as *const &'static ErrorVTable).read()
+}
+
+impl<E> ErrorImpl<E> {
+    fn erase(&self) -> Ref<'_, ErasedErrorImpl> {
+        // Erase the concrete type of E but preserve the vtable in self.vtable
+        // for manipulating the resulting thin pointer. This is analogous to an
+        // unsize coercion.
+        Ref::new(self).cast::<ErasedErrorImpl>()
+    }
+}
+
+impl ErasedErrorImpl {
+    pub(crate) unsafe fn error<'a>(
+        this: Ref<'a, Self>,
+    ) -> &'a (dyn StdError + Send + Sync + 'static) {
+        // Use vtable to attach E's native StdError vtable for the right
+        // original type E.
+        (vtable(this.ptr).object_ref_stderr)(this).deref()
+    }
+
+    pub(crate) unsafe fn diagnostic<'a>(
+        this: Ref<'a, Self>,
+    ) -> &'a (dyn Diagnostic + Send + Sync + 'static) {
+        // Use vtable to attach E's native StdError vtable for the right
+        // original type E.
+        (vtable(this.ptr).object_ref)(this).deref()
+    }
+
+    pub(crate) unsafe fn diagnostic_mut<'a>(
+        this: Mut<'a, Self>,
+    ) -> &'a mut (dyn Diagnostic + Send + Sync + 'static) {
+        // Use vtable to attach E's native StdError vtable for the right
+        // original type E.
+        (vtable(this.ptr).object_ref)(this.by_ref())
+            .by_mut()
+            .deref_mut()
+    }
+
+    pub(crate) unsafe fn chain(this: Ref<'_, Self>) -> Chain<'_> {
+        Chain::new(Self::error(this))
+    }
+}
+
+impl<E> StdError for ErrorImpl<E>
+where
+    E: StdError,
+{
+    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+        unsafe { ErrorImpl::diagnostic(self.erase()).source() }
+    }
+}
+
+impl<E> Diagnostic for ErrorImpl<E> where E: Diagnostic {}
+
+impl<E> Debug for ErrorImpl<E>
+where
+    E: Debug,
+{
+    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
+        unsafe { ErrorImpl::debug(self.erase(), formatter) }
+    }
+}
+
+impl<E> Display for ErrorImpl<E>
+where
+    E: Display,
+{
+    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
+        unsafe { Display::fmt(ErrorImpl::diagnostic(self.erase()), formatter) }
+    }
+}
+
+impl From<Report> for Box<dyn Diagnostic + Send + Sync + 'static> {
+    fn from(error: Report) -> Self {
+        let outer = ManuallyDrop::new(error);
+        unsafe {
+            // Use vtable to attach ErrorImpl<E>'s native StdError vtable for
+            // the right original type E.
+            (vtable(outer.inner.ptr).object_boxed)(outer.inner)
+        }
+    }
+}
+
+impl From<Report> for Box<dyn StdError + Send + Sync + 'static> {
+    fn from(error: Report) -> Self {
+        let outer = ManuallyDrop::new(error);
+        unsafe {
+            // Use vtable to attach ErrorImpl<E>'s native StdError vtable for
+            // the right original type E.
+            (vtable(outer.inner.ptr).object_boxed_stderr)(outer.inner)
+        }
+    }
+}
+
+impl From<Report> for Box<dyn Diagnostic + 'static> {
+    fn from(error: Report) -> Self {
+        Box::<dyn Diagnostic + Send + Sync>::from(error)
+    }
+}
+
+impl From<Report> for Box<dyn StdError + 'static> {
+    fn from(error: Report) -> Self {
+        Box::<dyn StdError + Send + Sync>::from(error)
+    }
+}
+
+impl AsRef<dyn Diagnostic + Send + Sync> for Report {
+    fn as_ref(&self) -> &(dyn Diagnostic + Send + Sync + 'static) {
+        &**self
+    }
+}
+
+impl AsRef<dyn Diagnostic> for Report {
+    fn as_ref(&self) -> &(dyn Diagnostic + 'static) {
+        &**self
+    }
+}
+
+impl AsRef<dyn StdError + Send + Sync> for Report {
+    fn as_ref(&self) -> &(dyn StdError + Send + Sync + 'static) {
+        unsafe { ErrorImpl::error(self.inner.by_ref()) }
+    }
+}
+
+impl AsRef<dyn StdError> for Report {
+    fn as_ref(&self) -> &(dyn StdError + 'static) {
+        unsafe { ErrorImpl::error(self.inner.by_ref()) }
+    }
+}
+
+impl std::borrow::Borrow<dyn Diagnostic> for Report {
+    fn borrow(&self) -> &(dyn Diagnostic + 'static) {
+        self.as_ref()
+    }
+}
diff --git a/src/eyreish/fmt.rs b/src/eyreish/fmt.rs
new file mode 100644
index 0000000..9e385d1
--- /dev/null
+++ b/src/eyreish/fmt.rs
@@ -0,0 +1,20 @@
+use super::{error::ErrorImpl, ptr::Ref};
+use core::fmt;
+
+impl ErrorImpl<()> {
+    pub(crate) unsafe fn display(this: Ref<'_, Self>, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        this.deref()
+            .handler
+            .as_ref()
+            .map(|handler| handler.display(Self::error(this), f))
+            .unwrap_or_else(|| core::fmt::Display::fmt(Self::diagnostic(this), f))
+    }
+
+    pub(crate) unsafe fn debug(this: Ref<'_, Self>, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        this.deref()
+            .handler
+            .as_ref()
+            .map(|handler| handler.debug(Self::diagnostic(this), f))
+            .unwrap_or_else(|| core::fmt::Debug::fmt(Self::diagnostic(this), f))
+    }
+}
diff --git a/src/eyreish/into_diagnostic.rs b/src/eyreish/into_diagnostic.rs
new file mode 100644
index 0000000..6480013
--- /dev/null
+++ b/src/eyreish/into_diagnostic.rs
@@ -0,0 +1,33 @@
+use thiserror::Error;
+
+use crate::{Diagnostic, Report};
+
+/// Convenience [`Diagnostic`] that can be used as an "anonymous" wrapper for
+/// Errors. This is intended to be paired with [`IntoDiagnostic`].
+#[derive(Debug, Error)]
+#[error(transparent)]
+struct DiagnosticError(Box<dyn std::error::Error + Send + Sync + 'static>);
+impl Diagnostic for DiagnosticError {}
+
+/**
+Convenience trait that adds a [`.into_diagnostic()`](IntoDiagnostic::into_diagnostic) method that converts a type implementing
+[`std::error::Error`] to a [`Result<T, Report>`].
+
+## Warning
+
+Calling this on a type implementing [`Diagnostic`] will reduce it to the common denominator of
+[`std::error::Error`]. Meaning all extra information provided by [`Diagnostic`] will be
+inaccessible. If you have a type implementing [`Diagnostic`] consider simply returning it or using
+[`Into`] or the [`Try`](std::ops::Try) operator (`?`).
+*/
+pub trait IntoDiagnostic<T, E> {
+    /// Converts [`Result`] types that return regular [`std::error::Error`]s
+    /// into a [`Result`] that returns a [`Diagnostic`].
+    fn into_diagnostic(self) -> Result<T, Report>;
+}
+
+impl<T, E: std::error::Error + Send + Sync + 'static> IntoDiagnostic<T, E> for Result<T, E> {
+    fn into_diagnostic(self) -> Result<T, Report> {
+        self.map_err(|e| DiagnosticError(Box::new(e)).into())
+    }
+}
diff --git a/src/eyreish/kind.rs b/src/eyreish/kind.rs
new file mode 100644
index 0000000..4eb9fef
--- /dev/null
+++ b/src/eyreish/kind.rs
@@ -0,0 +1,111 @@
+#![allow(missing_debug_implementations, missing_docs)]
+// Tagged dispatch mechanism for resolving the behavior of `miette!($expr)`.
+//
+// When miette! is given a single expr argument to turn into miette::Report, we
+// want the resulting Report to pick up the input's implementation of source()
+// and backtrace() if it has a std::error::Error impl, otherwise require nothing
+// more than Display and Debug.
+//
+// Expressed in terms of specialization, we want something like:
+//
+//     trait EyreNew {
+//         fn new(self) -> Report;
+//     }
+//
+//     impl<T> EyreNew for T
+//     where
+//         T: Display + Debug + Send + Sync + 'static,
+//     {
+//         default fn new(self) -> Report {
+//             /* no std error impl */
+//         }
+//     }
+//
+//     impl<T> EyreNew for T
+//     where
+//         T: std::error::Error + Send + Sync + 'static,
+//     {
+//         fn new(self) -> Report {
+//             /* use std error's source() and backtrace() */
+//         }
+//     }
+//
+// Since specialization is not stable yet, instead we rely on autoref behavior
+// of method resolution to perform tagged dispatch. Here we have two traits
+// AdhocKind and TraitKind that both have an miette_kind() method. AdhocKind is
+// implemented whether or not the caller's type has a std error impl, while
+// TraitKind is implemented only when a std error impl does exist. The ambiguity
+// is resolved by AdhocKind requiring an extra autoref so that it has lower
+// precedence.
+//
+// The miette! macro will set up the call in this form:
+//
+//     #[allow(unused_imports)]
+//     use $crate::private::{AdhocKind, TraitKind};
+//     let error = $msg;
+//     (&error).miette_kind().new(error)
+
+use super::Report;
+use core::fmt::{Debug, Display};
+
+use crate::Diagnostic;
+
+pub struct Adhoc;
+
+pub trait AdhocKind: Sized {
+    #[inline]
+    fn miette_kind(&self) -> Adhoc {
+        Adhoc
+    }
+}
+
+impl<T> AdhocKind for &T where T: ?Sized + Display + Debug + Send + Sync + 'static {}
+
+impl Adhoc {
+    #[cfg_attr(track_caller, track_caller)]
+    pub fn new<M>(self, message: M) -> Report
+    where
+        M: Display + Debug + Send + Sync + 'static,
+    {
+        Report::from_adhoc(message)
+    }
+}
+
+pub struct Trait;
+
+pub trait TraitKind: Sized {
+    #[inline]
+    fn miette_kind(&self) -> Trait {
+        Trait
+    }
+}
+
+impl<E> TraitKind for E where E: Into<Report> {}
+
+impl Trait {
+    #[cfg_attr(track_caller, track_caller)]
+    pub fn new<E>(self, error: E) -> Report
+    where
+        E: Into<Report>,
+    {
+        error.into()
+    }
+}
+
+pub struct Boxed;
+
+pub trait BoxedKind: Sized {
+    #[inline]
+    fn miette_kind(&self) -> Boxed {
+        Boxed
+    }
+}
+
+impl BoxedKind for Box<dyn Diagnostic + Send + Sync> {}
+
+impl Boxed {
+    #[cfg_attr(track_caller, track_caller)]
+    pub fn new(self, error: Box<dyn Diagnostic + Send + Sync>) -> Report {
+        Report::from_boxed(error)
+    }
+}
diff --git a/src/eyreish/macros.rs b/src/eyreish/macros.rs
new file mode 100644
index 0000000..938ac32
--- /dev/null
+++ b/src/eyreish/macros.rs
@@ -0,0 +1,295 @@
+/// Return early with an error.
+///
+/// This macro is equivalent to `return Err(From::from($err))`.
+///
+/// # Example
+///
+/// ```
+/// # use miette::{bail, Result};
+/// #
+/// # fn has_permission(user: usize, resource: usize) -> bool {
+/// #     true
+/// # }
+/// #
+/// # fn main() -> Result<()> {
+/// #     let user = 0;
+/// #     let resource = 0;
+/// #
+/// if !has_permission(user, resource) {
+#[cfg_attr(
+    not(feature = "no-format-args-capture"),
+    doc = r#"     bail!("permission denied for accessing {resource}");"#
+)]
+#[cfg_attr(
+    feature = "no-format-args-capture",
+    doc = r#"     bail!("permission denied for accessing {}", resource);"#
+)]
+/// }
+/// #     Ok(())
+/// # }
+/// ```
+///
+/// ```
+/// # use miette::{bail, Result};
+/// # use thiserror::Error;
+/// #
+/// # const MAX_DEPTH: usize = 1;
+/// #
+/// #[derive(Error, Debug)]
+/// enum ScienceError {
+///     #[error("recursion limit exceeded")]
+///     RecursionLimitExceeded,
+///     # #[error("...")]
+///     # More = (stringify! {
+///     ...
+///     # }, 1).1,
+/// }
+///
+/// # fn main() -> Result<()> {
+/// #     let depth = 0;
+/// #     let err: &'static dyn std::error::Error = &ScienceError::RecursionLimitExceeded;
+/// #
+/// if depth > MAX_DEPTH {
+///     bail!(ScienceError::RecursionLimitExceeded);
+/// }
+/// #     Ok(())
+/// # }
+/// ```
+///
+/// ```
+/// use miette::{bail, Result, Severity};
+///
+/// fn divide(x: f64, y: f64) -> Result<f64> {
+///     if y.abs() < 1e-3 {
+///         bail!(
+///             severity = Severity::Warning,
+#[cfg_attr(
+    not(feature = "no-format-args-capture"),
+    doc = r#"             "dividing by value ({y}) close to 0""#
+)]
+#[cfg_attr(
+    feature = "no-format-args-capture",
+    doc = r#"             "dividing by value ({}) close to 0", y"#
+)]
+///         );
+///     }
+///     Ok(x / y)
+/// }
+/// ```
+#[macro_export]
+macro_rules! bail {
+    ($($key:ident = $value:expr,)* $fmt:literal $($arg:tt)*) => {
+        return $crate::private::Err(
+            $crate::miette!($($key = $value,)* $fmt $($arg)*)
+        );
+    };
+    ($err:expr $(,)?) => {
+        return $crate::private::Err($crate::miette!($err));
+    };
+}
+
+/// Return early with an error if a condition is not satisfied.
+///
+/// This macro is equivalent to `if !$cond { return Err(From::from($err)); }`.
+///
+/// Analogously to `assert!`, `ensure!` takes a condition and exits the function
+/// if the condition fails. Unlike `assert!`, `ensure!` returns an `Error`
+/// rather than panicking.
+///
+/// # Example
+///
+/// ```
+/// # use miette::{ensure, Result};
+/// #
+/// # fn main() -> Result<()> {
+/// #     let user = 0;
+/// #
+/// ensure!(user == 0, "only user 0 is allowed");
+/// #     Ok(())
+/// # }
+/// ```
+///
+/// ```
+/// # use miette::{ensure, Result};
+/// # use thiserror::Error;
+/// #
+/// # const MAX_DEPTH: usize = 1;
+/// #
+/// #[derive(Error, Debug)]
+/// enum ScienceError {
+///     #[error("recursion limit exceeded")]
+///     RecursionLimitExceeded,
+///     # #[error("...")]
+///     # More = (stringify! {
+///     ...
+///     # }, 1).1,
+/// }
+///
+/// # fn main() -> Result<()> {
+/// #     let depth = 0;
+/// #
+/// ensure!(depth <= MAX_DEPTH, ScienceError::RecursionLimitExceeded);
+/// #     Ok(())
+/// # }
+/// ```
+///
+/// ```
+/// use miette::{ensure, Result, Severity};
+///
+/// fn divide(x: f64, y: f64) -> Result<f64> {
+///     ensure!(
+///         y.abs() >= 1e-3,
+///         severity = Severity::Warning,
+#[cfg_attr(
+    not(feature = "no-format-args-capture"),
+    doc = r#"             "dividing by value ({y}) close to 0""#
+)]
+#[cfg_attr(
+    feature = "no-format-args-capture",
+    doc = r#"             "dividing by value ({}) close to 0", y"#
+)]
+///     );
+///     Ok(x / y)
+/// }
+/// ```
+#[macro_export]
+macro_rules! ensure {
+    ($cond:expr, $($key:ident = $value:expr,)* $fmt:literal $($arg:tt)*) => {
+        if !$cond {
+            return $crate::private::Err(
+                $crate::miette!($($key = $value,)* $fmt $($arg)*)
+            );
+        }
+    };
+    ($cond:expr, $err:expr $(,)?) => {
+        if !$cond {
+            return $crate::private::Err($crate::miette!($err));
+        }
+    };
+}
+
+/// Construct an ad-hoc [`Report`].
+///
+/// # Examples
+///
+/// With string literal and interpolation:
+/// ```
+/// # use miette::miette;
+/// let x = 1;
+/// let y = 2;
+#[cfg_attr(
+    not(feature = "no-format-args-capture"),
+    doc = r#"let report = miette!("{x} + {} = {z}", y, z = x + y);"#
+)]
+#[cfg_attr(
+    feature = "no-format-args-capture",
+    doc = r#"let report = miette!("{} + {} = {z}", x, y, z = x + y);"#
+)]
+///
+/// assert_eq!(report.to_string().as_str(), "1 + 2 = 3");
+///
+/// let z = x + y;
+#[cfg_attr(
+    not(feature = "no-format-args-capture"),
+    doc = r#"let report = miette!("{x} + {y} = {z}");"#
+)]
+#[cfg_attr(
+    feature = "no-format-args-capture",
+    doc = r#"let report = miette!("{} + {} = {}", x, y, z);"#
+)]
+/// assert_eq!(report.to_string().as_str(), "1 + 2 = 3");
+/// ```
+///
+/// With [`diagnostic!`]-like arguments:
+/// ```
+/// use miette::{miette, LabeledSpan, Severity};
+///
+/// let source = "(2 + 2".to_string();
+/// let report = miette!(
+///     // Those fields are optional
+///     severity = Severity::Error,
+///     code = "expected::rparen",
+///     help = "always close your parens",
+///     labels = vec![LabeledSpan::at_offset(6, "here")],
+///     url = "https://example.com",
+///     // Rest of the arguments are passed to `format!`
+///     // to form diagnostic message
+///     "expected closing ')'"
+/// )
+/// .with_source_code(source);
+/// ```
+///
+/// ## `anyhow`/`eyre` Users
+///
+/// You can just replace `use`s of the `anyhow!`/`eyre!` macros with `miette!`.
+#[macro_export]
+macro_rules! miette {
+    ($($key:ident = $value:expr,)* $fmt:literal $($arg:tt)*) => {
+        $crate::Report::from(
+            $crate::diagnostic!($($key = $value,)* $fmt $($arg)*)
+        )
+    };
+    ($err:expr $(,)?) => ({
+        use $crate::private::kind::*;
+        let error = $err;
+        (&error).miette_kind().new(error)
+    });
+}
+
+/// Construct a [`MietteDiagnostic`] in more user-friendly way.
+///
+/// # Examples
+/// ```
+/// use miette::{diagnostic, LabeledSpan, Severity};
+///
+/// let source = "(2 + 2".to_string();
+/// let diag = diagnostic!(
+///     // Those fields are optional
+///     severity = Severity::Error,
+///     code = "expected::rparen",
+///     help = "always close your parens",
+///     labels = vec![LabeledSpan::at_offset(6, "here")],
+///     url = "https://example.com",
+///     // Rest of the arguments are passed to `format!`
+///     // to form diagnostic message
+///     "expected closing ')'",
+/// );
+/// ```
+/// Diagnostic without any fields:
+/// ```
+/// # use miette::diagnostic;
+/// let x = 1;
+/// let y = 2;
+///
+#[cfg_attr(
+    not(feature = "no-format-args-capture"),
+    doc = r#" let diag = diagnostic!("{x} + {} = {z}", y, z = x + y);"#
+)]
+#[cfg_attr(
+    feature = "no-format-args-capture",
+    doc = r#" let diag = diagnostic!("{} + {} = {z}", x, y, z = x + y);"#
+)]
+/// assert_eq!(diag.message, "1 + 2 = 3");
+///
+/// let z = x + y;
+#[cfg_attr(
+    not(feature = "no-format-args-capture"),
+    doc = r#"let diag = diagnostic!("{x} + {y} = {z}");"#
+)]
+#[cfg_attr(
+    feature = "no-format-args-capture",
+    doc = r#"let diag = diagnostic!("{} + {} = {}", x, y, z);"#
+)]
+/// assert_eq!(diag.message, "1 + 2 = 3");
+/// ```
+#[macro_export]
+macro_rules! diagnostic {
+    ($fmt:literal $($arg:tt)*) => {{
+        $crate::MietteDiagnostic::new(format!($fmt $($arg)*))
+    }};
+    ($($key:ident = $value:expr,)+ $fmt:literal $($arg:tt)*) => {{
+        let mut diag = $crate::MietteDiagnostic::new(format!($fmt $($arg)*));
+        $(diag.$key = Some($value.into());)*
+        diag
+    }};
+}
diff --git a/src/eyreish/mod.rs b/src/eyreish/mod.rs
new file mode 100644
index 0000000..0efceed
--- /dev/null
+++ b/src/eyreish/mod.rs
@@ -0,0 +1,485 @@
+#![cfg_attr(doc_cfg, feature(doc_cfg))]
+#![allow(
+    clippy::needless_doctest_main,
+    clippy::new_ret_no_self,
+    clippy::wrong_self_convention
+)]
+use core::fmt::Display;
+
+use std::error::Error as StdError;
+
+use once_cell::sync::OnceCell;
+
+#[allow(unreachable_pub)]
+pub use into_diagnostic::*;
+#[doc(hidden)]
+#[allow(unreachable_pub)]
+pub use Report as ErrReport;
+/// Compatibility re-export of `Report` for interop with `anyhow`
+#[allow(unreachable_pub)]
+pub use Report as Error;
+#[doc(hidden)]
+#[allow(unreachable_pub)]
+pub use ReportHandler as EyreContext;
+/// Compatibility re-export of `WrapErr` for interop with `anyhow`
+#[allow(unreachable_pub)]
+pub use WrapErr as Context;
+
+#[cfg(not(feature = "fancy-no-backtrace"))]
+use crate::DebugReportHandler;
+use crate::Diagnostic;
+#[cfg(feature = "fancy-no-backtrace")]
+use crate::MietteHandler;
+
+use error::ErrorImpl;
+
+use self::ptr::Own;
+
+mod context;
+mod error;
+mod fmt;
+mod into_diagnostic;
+mod kind;
+mod macros;
+mod ptr;
+mod wrapper;
+
+/**
+Core Diagnostic wrapper type.
+
+## `eyre` Users
+
+You can just replace `use`s of `eyre::Report` with `miette::Report`.
+*/
+pub struct Report {
+    inner: Own<ErrorImpl<()>>,
+}
+
+unsafe impl Sync for Report {}
+unsafe impl Send for Report {}
+
+///
+pub type ErrorHook =
+    Box<dyn Fn(&(dyn Diagnostic + 'static)) -> Box<dyn ReportHandler> + Sync + Send + 'static>;
+
+static HOOK: OnceCell<ErrorHook> = OnceCell::new();
+
+/// Error indicating that [`set_hook()`] was unable to install the provided
+/// [`ErrorHook`].
+#[derive(Debug)]
+pub struct InstallError;
+
+impl core::fmt::Display for InstallError {
+    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
+        f.write_str("cannot install provided ErrorHook, a hook has already been installed")
+    }
+}
+
+impl StdError for InstallError {}
+impl Diagnostic for InstallError {}
+
+/**
+Set the error hook.
+*/
+pub fn set_hook(hook: ErrorHook) -> Result<(), InstallError> {
+    HOOK.set(hook).map_err(|_| InstallError)
+}
+
+#[cfg_attr(track_caller, track_caller)]
+#[cfg_attr(not(track_caller), allow(unused_mut))]
+fn capture_handler(error: &(dyn Diagnostic + 'static)) -> Box<dyn ReportHandler> {
+    let hook = HOOK.get_or_init(|| Box::new(get_default_printer)).as_ref();
+
+    #[cfg(track_caller)]
+    {
+        let mut handler = hook(error);
+        handler.track_caller(std::panic::Location::caller());
+        handler
+    }
+    #[cfg(not(track_caller))]
+    {
+        hook(error)
+    }
+}
+
+fn get_default_printer(_err: &(dyn Diagnostic + 'static)) -> Box<dyn ReportHandler + 'static> {
+    #[cfg(feature = "fancy-no-backtrace")]
+    return Box::new(MietteHandler::new());
+    #[cfg(not(feature = "fancy-no-backtrace"))]
+    return Box::new(DebugReportHandler::new());
+}
+
+impl dyn ReportHandler {
+    ///
+    pub fn is<T: ReportHandler>(&self) -> bool {
+        // Get `TypeId` of the type this function is instantiated with.
+        let t = core::any::TypeId::of::<T>();
+
+        // Get `TypeId` of the type in the trait object (`self`).
+        let concrete = self.type_id();
+
+        // Compare both `TypeId`s on equality.
+        t == concrete
+    }
+
+    ///
+    pub fn downcast_ref<T: ReportHandler>(&self) -> Option<&T> {
+        if self.is::<T>() {
+            unsafe { Some(&*(self as *const dyn ReportHandler as *const T)) }
+        } else {
+            None
+        }
+    }
+
+    ///
+    pub fn downcast_mut<T: ReportHandler>(&mut self) -> Option<&mut T> {
+        if self.is::<T>() {
+            unsafe { Some(&mut *(self as *mut dyn ReportHandler as *mut T)) }
+        } else {
+            None
+        }
+    }
+}
+
+/// Error Report Handler trait for customizing `miette::Report`
+pub trait ReportHandler: core::any::Any + Send + Sync {
+    /// Define the report format
+    ///
+    /// Used to override the report format of `miette::Report`
+    ///
+    /// # Example
+    ///
+    /// ```rust
+    /// use indenter::indented;
+    /// use miette::{Diagnostic, ReportHandler};
+    ///
+    /// pub struct Handler;
+    ///
+    /// impl ReportHandler for Handler {
+    ///     fn debug(
+    ///         &self,
+    ///         error: &dyn Diagnostic,
+    ///         f: &mut core::fmt::Formatter<'_>,
+    ///     ) -> core::fmt::Result {
+    ///         use core::fmt::Write as _;
+    ///
+    ///         if f.alternate() {
+    ///             return core::fmt::Debug::fmt(error, f);
+    ///         }
+    ///
+    ///         write!(f, "{}", error)?;
+    ///
+    ///         Ok(())
+    ///     }
+    /// }
+    /// ```
+    fn debug(
+        &self,
+        error: &(dyn Diagnostic),
+        f: &mut core::fmt::Formatter<'_>,
+    ) -> core::fmt::Result;
+
+    /// Override for the `Display` format
+    fn display(
+        &self,
+        error: &(dyn StdError + 'static),
+        f: &mut core::fmt::Formatter<'_>,
+    ) -> core::fmt::Result {
+        write!(f, "{}", error)?;
+
+        if f.alternate() {
+            for cause in crate::chain::Chain::new(error).skip(1) {
+                write!(f, ": {}", cause)?;
+            }
+        }
+
+        Ok(())
+    }
+
+    /// Store the location of the caller who constructed this error report
+    #[allow(unused_variables)]
+    fn track_caller(&mut self, location: &'static std::panic::Location<'static>) {}
+}
+
+/// type alias for `Result<T, Report>`
+///
+/// This is a reasonable return type to use throughout your application but also
+/// for `main()`. If you do, failures will be printed along with a backtrace if
+/// one was captured.
+///
+/// `miette::Result` may be used with one *or* two type parameters.
+///
+/// ```rust
+/// use miette::Result;
+///
+/// # const IGNORE: &str = stringify! {
+/// fn demo1() -> Result<T> {...}
+///            // ^ equivalent to std::result::Result<T, miette::Error>
+///
+/// fn demo2() -> Result<T, OtherError> {...}
+///            // ^ equivalent to std::result::Result<T, OtherError>
+/// # };
+/// ```
+///
+/// # Example
+///
+/// ```
+/// # pub trait Deserialize {}
+/// #
+/// # mod serde_json {
+/// #     use super::Deserialize;
+/// #     use std::io;
+/// #
+/// #     pub fn from_str<T: Deserialize>(json: &str) -> io::Result<T> {
+/// #         unimplemented!()
+/// #     }
+/// # }
+/// #
+/// # #[derive(Debug)]
+/// # struct ClusterMap;
+/// #
+/// # impl Deserialize for ClusterMap {}
+/// #
+/// use miette::{IntoDiagnostic, Result};
+///
+/// fn main() -> Result<()> {
+///     # return Ok(());
+///     let config = std::fs::read_to_string("cluster.json").into_diagnostic()?;
+///     let map: ClusterMap = serde_json::from_str(&config).into_diagnostic()?;
+///     println!("cluster info: {:#?}", map);
+///     Ok(())
+/// }
+/// ```
+///
+/// ## `anyhow`/`eyre` Users
+///
+/// You can just replace `use`s of `anyhow::Result`/`eyre::Result` with
+/// `miette::Result`.
+pub type Result<T, E = Report> = core::result::Result<T, E>;
+
+/// Provides the [`wrap_err()`](WrapErr::wrap_err) method for [`Result`].
+///
+/// This trait is sealed and cannot be implemented for types outside of
+/// `miette`.
+///
+/// # Example
+///
+/// ```
+/// use miette::{WrapErr, IntoDiagnostic, Result};
+/// use std::{fs, path::PathBuf};
+///
+/// pub struct ImportantThing {
+///     path: PathBuf,
+/// }
+///
+/// impl ImportantThing {
+///     # const IGNORE: &'static str = stringify! {
+///     pub fn detach(&mut self) -> Result<()> {...}
+///     # };
+///     # fn detach(&mut self) -> Result<()> {
+///     #     unimplemented!()
+///     # }
+/// }
+///
+/// pub fn do_it(mut it: ImportantThing) -> Result<Vec<u8>> {
+///     it.detach().wrap_err("Failed to detach the important thing")?;
+///
+///     let path = &it.path;
+///     let content = fs::read(path)
+///         .into_diagnostic()
+///         .wrap_err_with(|| format!(
+///             "Failed to read instrs from {}",
+///             path.display())
+///         )?;
+///
+///     Ok(content)
+/// }
+/// ```
+///
+/// When printed, the outermost error would be printed first and the lower
+/// level underlying causes would be enumerated below.
+///
+/// ```console
+/// Error: Failed to read instrs from ./path/to/instrs.json
+///
+/// Caused by:
+///     No such file or directory (os error 2)
+/// ```
+///
+/// # Wrapping Types That Do Not Implement `Error`
+///
+/// For example `&str` and `Box<dyn Error>`.
+///
+/// Due to restrictions for coherence `Report` cannot implement `From` for types
+/// that don't implement `Error`. Attempts to do so will give `"this type might
+/// implement Error in the future"` as an error. As such, `wrap_err()`, which
+/// uses `From` under the hood, cannot be used to wrap these types. Instead we
+/// encourage you to use the combinators provided for `Result` in `std`/`core`.
+///
+/// For example, instead of this:
+///
+/// ```rust,compile_fail
+/// use std::error::Error;
+/// use miette::{WrapErr, Report};
+///
+/// fn wrap_example(err: Result<(), Box<dyn Error + Send + Sync + 'static>>)
+///     -> Result<(), Report>
+/// {
+///     err.wrap_err("saw a downstream error")
+/// }
+/// ```
+///
+/// We encourage you to write this:
+///
+/// ```rust
+/// use miette::{miette, Report, WrapErr};
+/// use std::error::Error;
+///
+/// fn wrap_example(err: Result<(), Box<dyn Error + Send + Sync + 'static>>) -> Result<(), Report> {
+///     err.map_err(|e| miette!(e))
+///         .wrap_err("saw a downstream error")
+/// }
+/// ```
+///
+/// # Effect on Downcasting
+///
+/// After attaching a message of type `D` onto an error of type `E`, the
+/// resulting `miette::Error` may be downcast to `D` **or** to `E`.
+///
+/// That is, in codebases that rely on downcasting, `miette`'s `wrap_err()`
+/// supports both of the following use cases:
+///
+///   - **Attaching messages whose type is insignificant onto errors whose type
+///     is used in downcasts.**
+///
+///     In other error libraries whose `wrap_err()` is not designed this way, it
+///     can be risky to introduce messages to existing code because new message
+///     might break existing working downcasts. In miette, any downcast that
+///     worked before adding the message will continue to work after you add a
+///     message, so you should freely wrap errors wherever it would be helpful.
+///
+///     ```
+///     # use miette::bail;
+///     # use thiserror::Error;
+///     #
+///     # #[derive(Error, Debug)]
+///     # #[error("???")]
+///     # struct SuspiciousError;
+///     #
+///     # fn helper() -> Result<()> {
+///     #     bail!(SuspiciousError);
+///     # }
+///     #
+///     use miette::{WrapErr, Result};
+///
+///     fn do_it() -> Result<()> {
+///         helper().wrap_err("Failed to complete the work")?;
+///         # const IGNORE: &str = stringify! {
+///         ...
+///         # };
+///         # unreachable!()
+///     }
+///
+///     fn main() {
+///         let err = do_it().unwrap_err();
+///         if let Some(e) = err.downcast_ref::<SuspiciousError>() {
+///             // If helper() returned SuspiciousError, this downcast will
+///             // correctly succeed even with the message in between.
+///             # return;
+///         }
+///         # panic!("expected downcast to succeed");
+///     }
+///     ```
+///
+///   - **Attaching message whose type is used in downcasts onto errors whose
+///     type is insignificant.**
+///
+///     Some codebases prefer to use machine-readable messages to categorize
+///     lower level errors in a way that will be actionable to higher levels of
+///     the application.
+///
+///     ```
+///     # use miette::bail;
+///     # use thiserror::Error;
+///     #
+///     # #[derive(Error, Debug)]
+///     # #[error("???")]
+///     # struct HelperFailed;
+///     #
+///     # fn helper() -> Result<()> {
+///     #     bail!("no such file or directory");
+///     # }
+///     #
+///     use miette::{WrapErr, Result};
+///
+///     fn do_it() -> Result<()> {
+///         helper().wrap_err(HelperFailed)?;
+///         # const IGNORE: &str = stringify! {
+///         ...
+///         # };
+///         # unreachable!()
+///     }
+///
+///     fn main() {
+///         let err = do_it().unwrap_err();
+///         if let Some(e) = err.downcast_ref::<HelperFailed>() {
+///             // If helper failed, this downcast will succeed because
+///             // HelperFailed is the message that has been attached to
+///             // that error.
+///             # return;
+///         }
+///         # panic!("expected downcast to succeed");
+///     }
+///     ```
+pub trait WrapErr<T, E>: context::private::Sealed {
+    /// Wrap the error value with a new adhoc error
+    #[cfg_attr(track_caller, track_caller)]
+    fn wrap_err<D>(self, msg: D) -> Result<T, Report>
+    where
+        D: Display + Send + Sync + 'static;
+
+    /// Wrap the error value with a new adhoc error that is evaluated lazily
+    /// only once an error does occur.
+    #[cfg_attr(track_caller, track_caller)]
+    fn wrap_err_with<D, F>(self, f: F) -> Result<T, Report>
+    where
+        D: Display + Send + Sync + 'static,
+        F: FnOnce() -> D;
+
+    /// Compatibility re-export of `wrap_err()` for interop with `anyhow`
+    #[cfg_attr(track_caller, track_caller)]
+    fn context<D>(self, msg: D) -> Result<T, Report>
+    where
+        D: Display + Send + Sync + 'static;
+
+    /// Compatibility re-export of `wrap_err_with()` for interop with `anyhow`
+    #[cfg_attr(track_caller, track_caller)]
+    fn with_context<D, F>(self, f: F) -> Result<T, Report>
+    where
+        D: Display + Send + Sync + 'static,
+        F: FnOnce() -> D;
+}
+
+// Private API. Referenced by macro-generated code.
+#[doc(hidden)]
+pub mod private {
+    use super::Report;
+    use core::fmt::{Debug, Display};
+
+    pub use core::result::Result::Err;
+
+    #[doc(hidden)]
+    pub mod kind {
+        pub use super::super::kind::{AdhocKind, TraitKind};
+
+        pub use super::super::kind::BoxedKind;
+    }
+
+    #[cfg_attr(track_caller, track_caller)]
+    pub fn new_adhoc<M>(message: M) -> Report
+    where
+        M: Display + Debug + Send + Sync + 'static,
+    {
+        Report::from_adhoc(message)
+    }
+}
diff --git a/src/eyreish/ptr.rs b/src/eyreish/ptr.rs
new file mode 100644
index 0000000..fa954d1
--- /dev/null
+++ b/src/eyreish/ptr.rs
@@ -0,0 +1,188 @@
+use std::{marker::PhantomData, ptr::NonNull};
+
+#[repr(transparent)]
+/// A raw pointer that owns its pointee
+pub(crate) struct Own<T>
+where
+    T: ?Sized,
+{
+    pub(crate) ptr: NonNull<T>,
+}
+
+unsafe impl<T> Send for Own<T> where T: ?Sized {}
+unsafe impl<T> Sync for Own<T> where T: ?Sized {}
+
+impl<T> Copy for Own<T> where T: ?Sized {}
+
+impl<T> Clone for Own<T>
+where
+    T: ?Sized,
+{
+    fn clone(&self) -> Self {
+        *self
+    }
+}
+
+impl<T> Own<T>
+where
+    T: ?Sized,
+{
+    pub(crate) fn new(ptr: Box<T>) -> Self {
+        Own {
+            ptr: unsafe { NonNull::new_unchecked(Box::into_raw(ptr)) },
+        }
+    }
+
+    pub(crate) fn cast<U: CastTo>(self) -> Own<U::Target> {
+        Own {
+            ptr: self.ptr.cast(),
+        }
+    }
+
+    pub(crate) unsafe fn boxed(self) -> Box<T> {
+        Box::from_raw(self.ptr.as_ptr())
+    }
+
+    pub(crate) const fn by_ref<'a>(&self) -> Ref<'a, T> {
+        Ref {
+            ptr: self.ptr,
+            lifetime: PhantomData,
+        }
+    }
+
+    pub(crate) fn by_mut<'a>(self) -> Mut<'a, T> {
+        Mut {
+            ptr: self.ptr,
+            lifetime: PhantomData,
+        }
+    }
+}
+
+#[allow(explicit_outlives_requirements)]
+#[repr(transparent)]
+/// A raw pointer that represents a shared borrow of its pointee
+pub(crate) struct Ref<'a, T>
+where
+    T: ?Sized,
+{
+    pub(crate) ptr: NonNull<T>,
+    lifetime: PhantomData<&'a T>,
+}
+
+impl<'a, T> Copy for Ref<'a, T> where T: ?Sized {}
+
+impl<'a, T> Clone for Ref<'a, T>
+where
+    T: ?Sized,
+{
+    fn clone(&self) -> Self {
+        *self
+    }
+}
+
+impl<'a, T> Ref<'a, T>
+where
+    T: ?Sized,
+{
+    pub(crate) fn new(ptr: &'a T) -> Self {
+        Ref {
+            ptr: NonNull::from(ptr),
+            lifetime: PhantomData,
+        }
+    }
+
+    pub(crate) const fn from_raw(ptr: NonNull<T>) -> Self {
+        Ref {
+            ptr,
+            lifetime: PhantomData,
+        }
+    }
+
+    pub(crate) fn cast<U: CastTo>(self) -> Ref<'a, U::Target> {
+        Ref {
+            ptr: self.ptr.cast(),
+            lifetime: PhantomData,
+        }
+    }
+
+    pub(crate) fn by_mut(self) -> Mut<'a, T> {
+        Mut {
+            ptr: self.ptr,
+            lifetime: PhantomData,
+        }
+    }
+
+    pub(crate) const fn as_ptr(self) -> *const T {
+        self.ptr.as_ptr() as *const T
+    }
+
+    pub(crate) unsafe fn deref(self) -> &'a T {
+        &*self.ptr.as_ptr()
+    }
+}
+
+#[allow(explicit_outlives_requirements)]
+#[repr(transparent)]
+/// A raw pointer that represents a unique borrow of its pointee
+pub(crate) struct Mut<'a, T>
+where
+    T: ?Sized,
+{
+    pub(crate) ptr: NonNull<T>,
+    lifetime: PhantomData<&'a mut T>,
+}
+
+impl<'a, T> Copy for Mut<'a, T> where T: ?Sized {}
+
+impl<'a, T> Clone for Mut<'a, T>
+where
+    T: ?Sized,
+{
+    fn clone(&self) -> Self {
+        *self
+    }
+}
+
+impl<'a, T> Mut<'a, T>
+where
+    T: ?Sized,
+{
+    pub(crate) fn cast<U: CastTo>(self) -> Mut<'a, U::Target> {
+        Mut {
+            ptr: self.ptr.cast(),
+            lifetime: PhantomData,
+        }
+    }
+
+    pub(crate) const fn by_ref(self) -> Ref<'a, T> {
+        Ref {
+            ptr: self.ptr,
+            lifetime: PhantomData,
+        }
+    }
+
+    pub(crate) fn extend<'b>(self) -> Mut<'b, T> {
+        Mut {
+            ptr: self.ptr,
+            lifetime: PhantomData,
+        }
+    }
+
+    pub(crate) unsafe fn deref_mut(self) -> &'a mut T {
+        &mut *self.ptr.as_ptr()
+    }
+}
+
+impl<'a, T> Mut<'a, T> {
+    pub(crate) unsafe fn read(self) -> T {
+        self.ptr.as_ptr().read()
+    }
+}
+
+pub(crate) trait CastTo {
+    type Target;
+}
+
+impl<T> CastTo for T {
+    type Target = T;
+}
diff --git a/src/eyreish/wrapper.rs b/src/eyreish/wrapper.rs
new file mode 100644
index 0000000..91a5ef3
--- /dev/null
+++ b/src/eyreish/wrapper.rs
@@ -0,0 +1,234 @@
+use core::fmt::{self, Debug, Display};
+
+use std::error::Error as StdError;
+
+use crate::{Diagnostic, LabeledSpan, Report, SourceCode};
+
+use crate as miette;
+
+#[repr(transparent)]
+pub(crate) struct DisplayError<M>(pub(crate) M);
+
+#[repr(transparent)]
+pub(crate) struct MessageError<M>(pub(crate) M);
+
+pub(crate) struct NoneError;
+
+impl<M> Debug for DisplayError<M>
+where
+    M: Display,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        Display::fmt(&self.0, f)
+    }
+}
+
+impl<M> Display for DisplayError<M>
+where
+    M: Display,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        Display::fmt(&self.0, f)
+    }
+}
+
+impl<M> StdError for DisplayError<M> where M: Display + 'static {}
+impl<M> Diagnostic for DisplayError<M> where M: Display + 'static {}
+
+impl<M> Debug for MessageError<M>
+where
+    M: Display + Debug,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        Debug::fmt(&self.0, f)
+    }
+}
+
+impl<M> Display for MessageError<M>
+where
+    M: Display + Debug,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        Display::fmt(&self.0, f)
+    }
+}
+
+impl<M> StdError for MessageError<M> where M: Display + Debug + 'static {}
+impl<M> Diagnostic for MessageError<M> where M: Display + Debug + 'static {}
+
+impl Debug for NoneError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        Debug::fmt("Option was None", f)
+    }
+}
+
+impl Display for NoneError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        Display::fmt("Option was None", f)
+    }
+}
+
+impl StdError for NoneError {}
+impl Diagnostic for NoneError {}
+
+#[repr(transparent)]
+pub(crate) struct BoxedError(pub(crate) Box<dyn Diagnostic + Send + Sync>);
+
+impl Diagnostic for BoxedError {
+    fn code<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        self.0.code()
+    }
+
+    fn severity(&self) -> Option<miette::Severity> {
+        self.0.severity()
+    }
+
+    fn help<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        self.0.help()
+    }
+
+    fn url<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        self.0.url()
+    }
+
+    fn labels<'a>(&'a self) -> Option<Box<dyn Iterator<Item = LabeledSpan> + 'a>> {
+        self.0.labels()
+    }
+
+    fn source_code(&self) -> Option<&dyn miette::SourceCode> {
+        self.0.source_code()
+    }
+
+    fn related<'a>(&'a self) -> Option<Box<dyn Iterator<Item = &'a dyn Diagnostic> + 'a>> {
+        self.0.related()
+    }
+
+    fn diagnostic_source(&self) -> Option<&dyn Diagnostic> {
+        self.0.diagnostic_source()
+    }
+}
+
+impl Debug for BoxedError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        Debug::fmt(&self.0, f)
+    }
+}
+
+impl Display for BoxedError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        Display::fmt(&self.0, f)
+    }
+}
+
+impl StdError for BoxedError {
+    fn source(&self) -> Option<&(dyn StdError + 'static)> {
+        self.0.source()
+    }
+
+    fn description(&self) -> &str {
+        #[allow(deprecated)]
+        self.0.description()
+    }
+
+    fn cause(&self) -> Option<&dyn StdError> {
+        #[allow(deprecated)]
+        self.0.cause()
+    }
+}
+
+pub(crate) struct WithSourceCode<E, C> {
+    pub(crate) error: E,
+    pub(crate) source_code: C,
+}
+
+impl<E: Diagnostic, C: SourceCode> Diagnostic for WithSourceCode<E, C> {
+    fn code<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        self.error.code()
+    }
+
+    fn severity(&self) -> Option<miette::Severity> {
+        self.error.severity()
+    }
+
+    fn help<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        self.error.help()
+    }
+
+    fn url<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        self.error.url()
+    }
+
+    fn labels<'a>(&'a self) -> Option<Box<dyn Iterator<Item = LabeledSpan> + 'a>> {
+        self.error.labels()
+    }
+
+    fn source_code(&self) -> Option<&dyn miette::SourceCode> {
+        Some(&self.source_code)
+    }
+
+    fn related<'a>(&'a self) -> Option<Box<dyn Iterator<Item = &'a dyn Diagnostic> + 'a>> {
+        self.error.related()
+    }
+
+    fn diagnostic_source(&self) -> Option<&dyn Diagnostic> {
+        self.error.diagnostic_source()
+    }
+}
+
+impl<C: SourceCode> Diagnostic for WithSourceCode<Report, C> {
+    fn code<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        self.error.code()
+    }
+
+    fn severity(&self) -> Option<miette::Severity> {
+        self.error.severity()
+    }
+
+    fn help<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        self.error.help()
+    }
+
+    fn url<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        self.error.url()
+    }
+
+    fn labels<'a>(&'a self) -> Option<Box<dyn Iterator<Item = LabeledSpan> + 'a>> {
+        self.error.labels()
+    }
+
+    fn source_code(&self) -> Option<&dyn miette::SourceCode> {
+        Some(&self.source_code)
+    }
+
+    fn related<'a>(&'a self) -> Option<Box<dyn Iterator<Item = &'a dyn Diagnostic> + 'a>> {
+        self.error.related()
+    }
+
+    fn diagnostic_source(&self) -> Option<&dyn Diagnostic> {
+        self.error.diagnostic_source()
+    }
+}
+
+impl<E: Debug, C> Debug for WithSourceCode<E, C> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        Debug::fmt(&self.error, f)
+    }
+}
+
+impl<E: Display, C> Display for WithSourceCode<E, C> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        Display::fmt(&self.error, f)
+    }
+}
+
+impl<E: StdError, C> StdError for WithSourceCode<E, C> {
+    fn source(&self) -> Option<&(dyn StdError + 'static)> {
+        self.error.source()
+    }
+}
+
+impl<C> StdError for WithSourceCode<Report, C> {
+    fn source(&self) -> Option<&(dyn StdError + 'static)> {
+        self.error.source()
+    }
+}
diff --git a/src/handler.rs b/src/handler.rs
new file mode 100644
index 0000000..e983a55
--- /dev/null
+++ b/src/handler.rs
@@ -0,0 +1,323 @@
+use std::fmt;
+
+use crate::protocol::Diagnostic;
+use crate::GraphicalReportHandler;
+use crate::GraphicalTheme;
+use crate::NarratableReportHandler;
+use crate::ReportHandler;
+use crate::ThemeCharacters;
+use crate::ThemeStyles;
+
+/// Settings to control the color format used for graphical rendering.
+#[derive(Copy, Clone, Debug, Eq, PartialEq)]
+pub enum RgbColors {
+    /// Use RGB colors even if the terminal does not support them
+    Always,
+    /// Use RGB colors instead of ANSI if the terminal supports RGB
+    Preferred,
+    /// Always use ANSI, regardless of terminal support for RGB
+    Never,
+}
+
+impl Default for RgbColors {
+    fn default() -> RgbColors {
+        RgbColors::Never
+    }
+}
+
+/**
+Create a custom [`MietteHandler`] from options.
+
+## Example
+
+```no_run
+miette::set_hook(Box::new(|_| {
+    Box::new(miette::MietteHandlerOpts::new()
+        .terminal_links(true)
+        .unicode(false)
+        .context_lines(3)
+        .build())
+}))
+# .unwrap();
+```
+*/
+#[derive(Default, Debug, Clone)]
+pub struct MietteHandlerOpts {
+    pub(crate) linkify: Option<bool>,
+    pub(crate) width: Option<usize>,
+    pub(crate) theme: Option<GraphicalTheme>,
+    pub(crate) force_graphical: Option<bool>,
+    pub(crate) force_narrated: Option<bool>,
+    pub(crate) rgb_colors: RgbColors,
+    pub(crate) color: Option<bool>,
+    pub(crate) unicode: Option<bool>,
+    pub(crate) footer: Option<String>,
+    pub(crate) context_lines: Option<usize>,
+    pub(crate) tab_width: Option<usize>,
+    pub(crate) with_cause_chain: Option<bool>,
+}
+
+impl MietteHandlerOpts {
+    /// Create a new `MietteHandlerOpts`.
+    pub fn new() -> Self {
+        Default::default()
+    }
+
+    /// If true, specify whether the graphical handler will make codes be
+    /// clickable links in supported terminals. Defaults to auto-detection
+    /// based on known supported terminals.
+    pub fn terminal_links(mut self, linkify: bool) -> Self {
+        self.linkify = Some(linkify);
+        self
+    }
+
+    /// Set a graphical theme for the handler when rendering in graphical mode.
+    /// Use [`force_graphical()`](`MietteHandlerOpts::force_graphical) to force
+    /// graphical mode. This option overrides
+    /// [`color()`](`MietteHandlerOpts::color).
+    pub fn graphical_theme(mut self, theme: GraphicalTheme) -> Self {
+        self.theme = Some(theme);
+        self
+    }
+
+    /// Sets the width to wrap the report at. Defaults to 80.
+    pub fn width(mut self, width: usize) -> Self {
+        self.width = Some(width);
+        self
+    }
+
+    /// Include the cause chain of the top-level error in the report.
+    pub fn with_cause_chain(mut self) -> Self {
+        self.with_cause_chain = Some(true);
+        self
+    }
+
+    /// Do not include the cause chain of the top-level error in the report.
+    pub fn without_cause_chain(mut self) -> Self {
+        self.with_cause_chain = Some(false);
+        self
+    }
+
+    /// If true, colors will be used during graphical rendering, regardless
+    /// of whether or not the terminal supports them.
+    ///
+    /// If false, colors will never be used.
+    ///
+    /// If unspecified, colors will be used only if the terminal supports them.
+    ///
+    /// The actual format depends on the value of
+    /// [`MietteHandlerOpts::rgb_colors`].
+    pub fn color(mut self, color: bool) -> Self {
+        self.color = Some(color);
+        self
+    }
+
+    /// Controls which color format to use if colors are used in graphical
+    /// rendering.
+    ///
+    /// The default is `Never`.
+    ///
+    /// This value does not control whether or not colors are being used in the
+    /// first place. That is handled by the [`MietteHandlerOpts::color`]
+    /// setting. If colors are not being used, the value of `rgb_colors` has
+    /// no effect.
+    pub fn rgb_colors(mut self, color: RgbColors) -> Self {
+        self.rgb_colors = color;
+        self
+    }
+
+    /// If true, forces unicode display for graphical output. If set to false,
+    /// forces ASCII art display.
+    pub fn unicode(mut self, unicode: bool) -> Self {
+        self.unicode = Some(unicode);
+        self
+    }
+
+    /// If true, graphical rendering will be used regardless of terminal
+    /// detection.
+    pub fn force_graphical(mut self, force: bool) -> Self {
+        self.force_graphical = Some(force);
+        self
+    }
+
+    /// If true, forces use of the narrated renderer.
+    pub fn force_narrated(mut self, force: bool) -> Self {
+        self.force_narrated = Some(force);
+        self
+    }
+
+    /// Set a footer to be displayed at the bottom of the report.
+    pub fn footer(mut self, footer: String) -> Self {
+        self.footer = Some(footer);
+        self
+    }
+
+    /// Sets the number of context lines before and after a span to display.
+    pub fn context_lines(mut self, context_lines: usize) -> Self {
+        self.context_lines = Some(context_lines);
+        self
+    }
+
+    /// Set the displayed tab width in spaces.
+    pub fn tab_width(mut self, width: usize) -> Self {
+        self.tab_width = Some(width);
+        self
+    }
+
+    /// Builds a [`MietteHandler`] from this builder.
+    pub fn build(self) -> MietteHandler {
+        let graphical = self.is_graphical();
+        let width = self.get_width();
+        if !graphical {
+            let mut handler = NarratableReportHandler::new();
+            if let Some(footer) = self.footer {
+                handler = handler.with_footer(footer);
+            }
+            if let Some(context_lines) = self.context_lines {
+                handler = handler.with_context_lines(context_lines);
+            }
+            if let Some(with_cause_chain) = self.with_cause_chain {
+                if with_cause_chain {
+                    handler = handler.with_cause_chain();
+                } else {
+                    handler = handler.without_cause_chain();
+                }
+            }
+            MietteHandler {
+                inner: Box::new(handler),
+            }
+        } else {
+            let linkify = self.use_links();
+            let characters = match self.unicode {
+                Some(true) => ThemeCharacters::unicode(),
+                Some(false) => ThemeCharacters::ascii(),
+                None if supports_unicode::on(supports_unicode::Stream::Stderr) => {
+                    ThemeCharacters::unicode()
+                }
+                None => ThemeCharacters::ascii(),
+            };
+            let styles = if self.color == Some(false) {
+                ThemeStyles::none()
+            } else if let Some(color) = supports_color::on(supports_color::Stream::Stderr) {
+                match self.rgb_colors {
+                    RgbColors::Always => ThemeStyles::rgb(),
+                    RgbColors::Preferred if color.has_16m => ThemeStyles::rgb(),
+                    _ => ThemeStyles::ansi(),
+                }
+            } else if self.color == Some(true) {
+                match self.rgb_colors {
+                    RgbColors::Always => ThemeStyles::rgb(),
+                    _ => ThemeStyles::ansi(),
+                }
+            } else {
+                ThemeStyles::none()
+            };
+            let theme = self.theme.unwrap_or(GraphicalTheme { characters, styles });
+            let mut handler = GraphicalReportHandler::new()
+                .with_width(width)
+                .with_links(linkify)
+                .with_theme(theme);
+            if let Some(with_cause_chain) = self.with_cause_chain {
+                if with_cause_chain {
+                    handler = handler.with_cause_chain();
+                } else {
+                    handler = handler.without_cause_chain();
+                }
+            }
+            if let Some(footer) = self.footer {
+                handler = handler.with_footer(footer);
+            }
+            if let Some(context_lines) = self.context_lines {
+                handler = handler.with_context_lines(context_lines);
+            }
+            if let Some(w) = self.tab_width {
+                handler = handler.tab_width(w);
+            }
+            MietteHandler {
+                inner: Box::new(handler),
+            }
+        }
+    }
+
+    pub(crate) fn is_graphical(&self) -> bool {
+        if let Some(force_narrated) = self.force_narrated {
+            !force_narrated
+        } else if let Some(force_graphical) = self.force_graphical {
+            force_graphical
+        } else if let Ok(env) = std::env::var("NO_GRAPHICS") {
+            env == "0"
+        } else {
+            true
+        }
+    }
+
+    // Detects known terminal apps based on env variables and returns true if
+    // they support rendering links.
+    pub(crate) fn use_links(&self) -> bool {
+        if let Some(linkify) = self.linkify {
+            linkify
+        } else {
+            supports_hyperlinks::on(supports_hyperlinks::Stream::Stderr)
+        }
+    }
+
+    #[cfg(not(miri))]
+    pub(crate) fn get_width(&self) -> usize {
+        self.width.unwrap_or_else(|| {
+            terminal_size::terminal_size()
+                .unwrap_or((terminal_size::Width(80), terminal_size::Height(0)))
+                .0
+                 .0 as usize
+        })
+    }
+
+    #[cfg(miri)]
+    // miri doesn't support a syscall (specifically ioctl)
+    // performed by terminal_size, which causes test execution to fail
+    // so when miri is running we'll just fallback to a constant
+    pub(crate) fn get_width(&self) -> usize {
+        self.width.unwrap_or(80)
+    }
+}
+
+/**
+A [`ReportHandler`] that displays a given [`Report`](crate::Report) in a
+quasi-graphical way, using terminal colors, unicode drawing characters, and
+other such things.
+
+This is the default reporter bundled with `miette`.
+
+This printer can be customized by using
+[`GraphicalReportHandler::new_themed()`] and handing it a [`GraphicalTheme`] of
+your own creation (or using one of its own defaults).
+
+See [`set_hook`](crate::set_hook) for more details on customizing your global
+printer.
+*/
+#[allow(missing_debug_implementations)]
+pub struct MietteHandler {
+    inner: Box<dyn ReportHandler + Send + Sync>,
+}
+
+impl MietteHandler {
+    /// Creates a new [`MietteHandler`] with default settings.
+    pub fn new() -> Self {
+        Default::default()
+    }
+}
+
+impl Default for MietteHandler {
+    fn default() -> Self {
+        MietteHandlerOpts::new().build()
+    }
+}
+
+impl ReportHandler for MietteHandler {
+    fn debug(&self, diagnostic: &(dyn Diagnostic), f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        if f.alternate() {
+            return fmt::Debug::fmt(diagnostic, f);
+        }
+
+        self.inner.debug(diagnostic, f)
+    }
+}
diff --git a/src/handlers/debug.rs b/src/handlers/debug.rs
new file mode 100644
index 0000000..50450a4
--- /dev/null
+++ b/src/handlers/debug.rs
@@ -0,0 +1,71 @@
+use std::fmt;
+
+use crate::{protocol::Diagnostic, ReportHandler};
+
+/**
+[`ReportHandler`] that renders plain text and avoids extraneous graphics.
+It's optimized for screen readers and braille users, but is also used in any
+non-graphical environments, such as non-TTY output.
+*/
+#[derive(Debug, Clone)]
+pub struct DebugReportHandler;
+
+impl DebugReportHandler {
+    /// Create a new [`NarratableReportHandler`](crate::NarratableReportHandler)
+    /// There are no customization options.
+    pub const fn new() -> Self {
+        Self
+    }
+}
+
+impl Default for DebugReportHandler {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl DebugReportHandler {
+    /// Render a [`Diagnostic`]. This function is mostly internal and meant to
+    /// be called by the toplevel [`ReportHandler`] handler, but is made public
+    /// to make it easier (possible) to test in isolation from global state.
+    pub fn render_report(
+        &self,
+        f: &mut fmt::Formatter<'_>,
+        diagnostic: &(dyn Diagnostic),
+    ) -> fmt::Result {
+        let mut diag = f.debug_struct("Diagnostic");
+        diag.field("message", &format!("{}", diagnostic));
+        if let Some(code) = diagnostic.code() {
+            diag.field("code", &code.to_string());
+        }
+        if let Some(severity) = diagnostic.severity() {
+            diag.field("severity", &format!("{:?}", severity));
+        }
+        if let Some(url) = diagnostic.url() {
+            diag.field("url", &url.to_string());
+        }
+        if let Some(help) = diagnostic.help() {
+            diag.field("help", &help.to_string());
+        }
+        if let Some(labels) = diagnostic.labels() {
+            let labels: Vec<_> = labels.collect();
+            diag.field("labels", &format!("{:?}", labels));
+        }
+        if let Some(cause) = diagnostic.diagnostic_source() {
+            diag.field("caused by", &format!("{:?}", cause));
+        }
+        diag.finish()?;
+        writeln!(f)?;
+        writeln!(f, "NOTE: If you're looking for the fancy error reports, install miette with the `fancy` feature, or write your own and hook it up with miette::set_hook().")
+    }
+}
+
+impl ReportHandler for DebugReportHandler {
+    fn debug(&self, diagnostic: &(dyn Diagnostic), f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        if f.alternate() {
+            return fmt::Debug::fmt(diagnostic, f);
+        }
+
+        self.render_report(f, diagnostic)
+    }
+}
diff --git a/src/handlers/graphical.rs b/src/handlers/graphical.rs
new file mode 100644
index 0000000..b5dd754
--- /dev/null
+++ b/src/handlers/graphical.rs
@@ -0,0 +1,920 @@
+use std::fmt::{self, Write};
+
+use owo_colors::{OwoColorize, Style};
+use unicode_width::UnicodeWidthChar;
+
+use crate::diagnostic_chain::{DiagnosticChain, ErrorKind};
+use crate::handlers::theme::*;
+use crate::protocol::{Diagnostic, Severity};
+use crate::{LabeledSpan, MietteError, ReportHandler, SourceCode, SourceSpan, SpanContents};
+
+/**
+A [`ReportHandler`] that displays a given [`Report`](crate::Report) in a
+quasi-graphical way, using terminal colors, unicode drawing characters, and
+other such things.
+
+This is the default reporter bundled with `miette`.
+
+This printer can be customized by using [`new_themed()`](GraphicalReportHandler::new_themed) and handing it a
+[`GraphicalTheme`] of your own creation (or using one of its own defaults!)
+
+See [`set_hook()`](crate::set_hook) for more details on customizing your global
+printer.
+*/
+#[derive(Debug, Clone)]
+pub struct GraphicalReportHandler {
+    pub(crate) links: LinkStyle,
+    pub(crate) termwidth: usize,
+    pub(crate) theme: GraphicalTheme,
+    pub(crate) footer: Option<String>,
+    pub(crate) context_lines: usize,
+    pub(crate) tab_width: usize,
+    pub(crate) with_cause_chain: bool,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub(crate) enum LinkStyle {
+    None,
+    Link,
+    Text,
+}
+
+impl GraphicalReportHandler {
+    /// Create a new `GraphicalReportHandler` with the default
+    /// [`GraphicalTheme`]. This will use both unicode characters and colors.
+    pub fn new() -> Self {
+        Self {
+            links: LinkStyle::Link,
+            termwidth: 200,
+            theme: GraphicalTheme::default(),
+            footer: None,
+            context_lines: 1,
+            tab_width: 4,
+            with_cause_chain: true,
+        }
+    }
+
+    ///Create a new `GraphicalReportHandler` with a given [`GraphicalTheme`].
+    pub fn new_themed(theme: GraphicalTheme) -> Self {
+        Self {
+            links: LinkStyle::Link,
+            termwidth: 200,
+            theme,
+            footer: None,
+            context_lines: 1,
+            tab_width: 4,
+            with_cause_chain: true,
+        }
+    }
+
+    /// Set the displayed tab width in spaces.
+    pub fn tab_width(mut self, width: usize) -> Self {
+        self.tab_width = width;
+        self
+    }
+
+    /// Whether to enable error code linkification using [`Diagnostic::url()`].
+    pub fn with_links(mut self, links: bool) -> Self {
+        self.links = if links {
+            LinkStyle::Link
+        } else {
+            LinkStyle::Text
+        };
+        self
+    }
+
+    /// Include the cause chain of the top-level error in the graphical output,
+    /// if available.
+    pub fn with_cause_chain(mut self) -> Self {
+        self.with_cause_chain = true;
+        self
+    }
+
+    /// Do not include the cause chain of the top-level error in the graphical
+    /// output.
+    pub fn without_cause_chain(mut self) -> Self {
+        self.with_cause_chain = false;
+        self
+    }
+
+    /// Whether to include [`Diagnostic::url()`] in the output.
+    ///
+    /// Disabling this is not recommended, but can be useful for more easily
+    /// reproducible tests, as `url(docsrs)` links are version-dependent.
+    pub fn with_urls(mut self, urls: bool) -> Self {
+        self.links = match (self.links, urls) {
+            (_, false) => LinkStyle::None,
+            (LinkStyle::None, true) => LinkStyle::Link,
+            (links, true) => links,
+        };
+        self
+    }
+
+    /// Set a theme for this handler.
+    pub fn with_theme(mut self, theme: GraphicalTheme) -> Self {
+        self.theme = theme;
+        self
+    }
+
+    /// Sets the width to wrap the report at.
+    pub fn with_width(mut self, width: usize) -> Self {
+        self.termwidth = width;
+        self
+    }
+
+    /// Sets the 'global' footer for this handler.
+    pub fn with_footer(mut self, footer: String) -> Self {
+        self.footer = Some(footer);
+        self
+    }
+
+    /// Sets the number of lines of context to show around each error.
+    pub fn with_context_lines(mut self, lines: usize) -> Self {
+        self.context_lines = lines;
+        self
+    }
+}
+
+impl Default for GraphicalReportHandler {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl GraphicalReportHandler {
+    /// Render a [`Diagnostic`]. This function is mostly internal and meant to
+    /// be called by the toplevel [`ReportHandler`] handler, but is made public
+    /// to make it easier (possible) to test in isolation from global state.
+    pub fn render_report(
+        &self,
+        f: &mut impl fmt::Write,
+        diagnostic: &(dyn Diagnostic),
+    ) -> fmt::Result {
+        self.render_header(f, diagnostic)?;
+        self.render_causes(f, diagnostic)?;
+        let src = diagnostic.source_code();
+        self.render_snippets(f, diagnostic, src)?;
+        self.render_footer(f, diagnostic)?;
+        self.render_related(f, diagnostic, src)?;
+        if let Some(footer) = &self.footer {
+            writeln!(f)?;
+            let width = self.termwidth.saturating_sub(4);
+            let opts = textwrap::Options::new(width)
+                .initial_indent("  ")
+                .subsequent_indent("  ");
+            writeln!(f, "{}", textwrap::fill(footer, opts))?;
+        }
+        Ok(())
+    }
+
+    fn render_header(&self, f: &mut impl fmt::Write, diagnostic: &(dyn Diagnostic)) -> fmt::Result {
+        let severity_style = match diagnostic.severity() {
+            Some(Severity::Error) | None => self.theme.styles.error,
+            Some(Severity::Warning) => self.theme.styles.warning,
+            Some(Severity::Advice) => self.theme.styles.advice,
+        };
+        let mut header = String::new();
+        if self.links == LinkStyle::Link && diagnostic.url().is_some() {
+            let url = diagnostic.url().unwrap(); // safe
+            let code = if let Some(code) = diagnostic.code() {
+                format!("{} ", code)
+            } else {
+                "".to_string()
+            };
+            let link = format!(
+                "\u{1b}]8;;{}\u{1b}\\{}{}\u{1b}]8;;\u{1b}\\",
+                url,
+                code.style(severity_style),
+                "(link)".style(self.theme.styles.link)
+            );
+            write!(header, "{}", link)?;
+            writeln!(f, "{}", header)?;
+            writeln!(f)?;
+        } else if let Some(code) = diagnostic.code() {
+            write!(header, "{}", code.style(severity_style),)?;
+            if self.links == LinkStyle::Text && diagnostic.url().is_some() {
+                let url = diagnostic.url().unwrap(); // safe
+                write!(header, " ({})", url.style(self.theme.styles.link))?;
+            }
+            writeln!(f, "{}", header)?;
+            writeln!(f)?;
+        }
+        Ok(())
+    }
+
+    fn render_causes(&self, f: &mut impl fmt::Write, diagnostic: &(dyn Diagnostic)) -> fmt::Result {
+        let (severity_style, severity_icon) = match diagnostic.severity() {
+            Some(Severity::Error) | None => (self.theme.styles.error, &self.theme.characters.error),
+            Some(Severity::Warning) => (self.theme.styles.warning, &self.theme.characters.warning),
+            Some(Severity::Advice) => (self.theme.styles.advice, &self.theme.characters.advice),
+        };
+
+        let initial_indent = format!("  {} ", severity_icon.style(severity_style));
+        let rest_indent = format!("  {} ", self.theme.characters.vbar.style(severity_style));
+        let width = self.termwidth.saturating_sub(2);
+        let opts = textwrap::Options::new(width)
+            .initial_indent(&initial_indent)
+            .subsequent_indent(&rest_indent);
+
+        writeln!(f, "{}", textwrap::fill(&diagnostic.to_string(), opts))?;
+
+        if !self.with_cause_chain {
+            return Ok(());
+        }
+
+        if let Some(mut cause_iter) = diagnostic
+            .diagnostic_source()
+            .map(DiagnosticChain::from_diagnostic)
+            .or_else(|| diagnostic.source().map(DiagnosticChain::from_stderror))
+            .map(|it| it.peekable())
+        {
+            while let Some(error) = cause_iter.next() {
+                let is_last = cause_iter.peek().is_none();
+                let char = if !is_last {
+                    self.theme.characters.lcross
+                } else {
+                    self.theme.characters.lbot
+                };
+                let initial_indent = format!(
+                    "  {}{}{} ",
+                    char, self.theme.characters.hbar, self.theme.characters.rarrow
+                )
+                .style(severity_style)
+                .to_string();
+                let rest_indent = format!(
+                    "  {}   ",
+                    if is_last {
+                        ' '
+                    } else {
+                        self.theme.characters.vbar
+                    }
+                )
+                .style(severity_style)
+                .to_string();
+                let opts = textwrap::Options::new(width)
+                    .initial_indent(&initial_indent)
+                    .subsequent_indent(&rest_indent);
+                match error {
+                    ErrorKind::Diagnostic(diag) => {
+                        let mut inner = String::new();
+
+                        // Don't print footer for inner errors
+                        let mut inner_renderer = self.clone();
+                        inner_renderer.footer = None;
+                        inner_renderer.with_cause_chain = false;
+                        inner_renderer.render_report(&mut inner, diag)?;
+
+                        writeln!(f, "{}", textwrap::fill(&inner, opts))?;
+                    }
+                    ErrorKind::StdError(err) => {
+                        writeln!(f, "{}", textwrap::fill(&err.to_string(), opts))?;
+                    }
+                }
+            }
+        }
+
+        Ok(())
+    }
+
+    fn render_footer(&self, f: &mut impl fmt::Write, diagnostic: &(dyn Diagnostic)) -> fmt::Result {
+        if let Some(help) = diagnostic.help() {
+            let width = self.termwidth.saturating_sub(4);
+            let initial_indent = "  help: ".style(self.theme.styles.help).to_string();
+            let opts = textwrap::Options::new(width)
+                .initial_indent(&initial_indent)
+                .subsequent_indent("        ");
+            writeln!(f, "{}", textwrap::fill(&help.to_string(), opts))?;
+        }
+        Ok(())
+    }
+
+    fn render_related(
+        &self,
+        f: &mut impl fmt::Write,
+        diagnostic: &(dyn Diagnostic),
+        parent_src: Option<&dyn SourceCode>,
+    ) -> fmt::Result {
+        if let Some(related) = diagnostic.related() {
+            writeln!(f)?;
+            for rel in related {
+                match rel.severity() {
+                    Some(Severity::Error) | None => write!(f, "Error: ")?,
+                    Some(Severity::Warning) => write!(f, "Warning: ")?,
+                    Some(Severity::Advice) => write!(f, "Advice: ")?,
+                };
+                self.render_header(f, rel)?;
+                self.render_causes(f, rel)?;
+                let src = rel.source_code().or(parent_src);
+                self.render_snippets(f, rel, src)?;
+                self.render_footer(f, rel)?;
+                self.render_related(f, rel, src)?;
+            }
+        }
+        Ok(())
+    }
+
+    fn render_snippets(
+        &self,
+        f: &mut impl fmt::Write,
+        diagnostic: &(dyn Diagnostic),
+        opt_source: Option<&dyn SourceCode>,
+    ) -> fmt::Result {
+        if let Some(source) = opt_source {
+            if let Some(labels) = diagnostic.labels() {
+                let mut labels = labels.collect::<Vec<_>>();
+                labels.sort_unstable_by_key(|l| l.inner().offset());
+                if !labels.is_empty() {
+                    let contents = labels
+                        .iter()
+                        .map(|label| {
+                            source.read_span(label.inner(), self.context_lines, self.context_lines)
+                        })
+                        .collect::<Result<Vec<Box<dyn SpanContents<'_>>>, MietteError>>()
+                        .map_err(|_| fmt::Error)?;
+                    let mut contexts = Vec::with_capacity(contents.len());
+                    for (right, right_conts) in labels.iter().cloned().zip(contents.iter()) {
+                        if contexts.is_empty() {
+                            contexts.push((right, right_conts));
+                        } else {
+                            let (left, left_conts) = contexts.last().unwrap().clone();
+                            let left_end = left.offset() + left.len();
+                            let right_end = right.offset() + right.len();
+                            if left_conts.line() + left_conts.line_count() >= right_conts.line() {
+                                // The snippets will overlap, so we create one Big Chunky Boi
+                                let new_span = LabeledSpan::new(
+                                    left.label().map(String::from),
+                                    left.offset(),
+                                    if right_end >= left_end {
+                                        // Right end goes past left end
+                                        right_end - left.offset()
+                                    } else {
+                                        // right is contained inside left
+                                        left.len()
+                                    },
+                                );
+                                if source
+                                    .read_span(
+                                        new_span.inner(),
+                                        self.context_lines,
+                                        self.context_lines,
+                                    )
+                                    .is_ok()
+                                {
+                                    contexts.pop();
+                                    contexts.push((
+                                        // We'll throw this away later
+                                        new_span, left_conts,
+                                    ));
+                                } else {
+                                    contexts.push((right, right_conts));
+                                }
+                            } else {
+                                contexts.push((right, right_conts));
+                            }
+                        }
+                    }
+                    for (ctx, _) in contexts {
+                        self.render_context(f, source, &ctx, &labels[..])?;
+                    }
+                }
+            }
+        }
+        Ok(())
+    }
+
+    fn render_context<'a>(
+        &self,
+        f: &mut impl fmt::Write,
+        source: &'a dyn SourceCode,
+        context: &LabeledSpan,
+        labels: &[LabeledSpan],
+    ) -> fmt::Result {
+        let (contents, lines) = self.get_lines(source, context.inner())?;
+
+        // sorting is your friend
+        let labels = labels
+            .iter()
+            .zip(self.theme.styles.highlights.iter().cloned().cycle())
+            .map(|(label, st)| FancySpan::new(label.label().map(String::from), *label.inner(), st))
+            .collect::<Vec<_>>();
+
+        // The max number of gutter-lines that will be active at any given
+        // point. We need this to figure out indentation, so we do one loop
+        // over the lines to see what the damage is gonna be.
+        let mut max_gutter = 0usize;
+        for line in &lines {
+            let mut num_highlights = 0;
+            for hl in &labels {
+                if !line.span_line_only(hl) && line.span_applies(hl) {
+                    num_highlights += 1;
+                }
+            }
+            max_gutter = std::cmp::max(max_gutter, num_highlights);
+        }
+
+        // Oh and one more thing: We need to figure out how much room our line
+        // numbers need!
+        let linum_width = lines[..]
+            .last()
+            .map(|line| line.line_number)
+            // It's possible for the source to be an empty string.
+            .unwrap_or(0)
+            .to_string()
+            .len();
+
+        // Header
+        write!(
+            f,
+            "{}{}{}",
+            " ".repeat(linum_width + 2),
+            self.theme.characters.ltop,
+            self.theme.characters.hbar,
+        )?;
+
+        if let Some(source_name) = contents.name() {
+            let source_name = source_name.style(self.theme.styles.link);
+            writeln!(
+                f,
+                "[{}:{}:{}]",
+                source_name,
+                contents.line() + 1,
+                contents.column() + 1
+            )?;
+        } else if lines.len() <= 1 {
+            writeln!(f, "{}", self.theme.characters.hbar.to_string().repeat(3))?;
+        } else {
+            writeln!(f, "[{}:{}]", contents.line() + 1, contents.column() + 1)?;
+        }
+
+        // Now it's time for the fun part--actually rendering everything!
+        for line in &lines {
+            // Line number, appropriately padded.
+            self.write_linum(f, linum_width, line.line_number)?;
+
+            // Then, we need to print the gutter, along with any fly-bys We
+            // have separate gutters depending on whether we're on the actual
+            // line, or on one of the "highlight lines" below it.
+            self.render_line_gutter(f, max_gutter, line, &labels)?;
+
+            // And _now_ we can print out the line text itself!
+            self.render_line_text(f, &line.text)?;
+
+            // Next, we write all the highlights that apply to this particular line.
+            let (single_line, multi_line): (Vec<_>, Vec<_>) = labels
+                .iter()
+                .filter(|hl| line.span_applies(hl))
+                .partition(|hl| line.span_line_only(hl));
+            if !single_line.is_empty() {
+                // no line number!
+                self.write_no_linum(f, linum_width)?;
+                // gutter _again_
+                self.render_highlight_gutter(f, max_gutter, line, &labels)?;
+                self.render_single_line_highlights(
+                    f,
+                    line,
+                    linum_width,
+                    max_gutter,
+                    &single_line,
+                    &labels,
+                )?;
+            }
+            for hl in multi_line {
+                if hl.label().is_some() && line.span_ends(hl) && !line.span_starts(hl) {
+                    // no line number!
+                    self.write_no_linum(f, linum_width)?;
+                    // gutter _again_
+                    self.render_highlight_gutter(f, max_gutter, line, &labels)?;
+                    self.render_multi_line_end(f, hl)?;
+                }
+            }
+        }
+        writeln!(
+            f,
+            "{}{}{}",
+            " ".repeat(linum_width + 2),
+            self.theme.characters.lbot,
+            self.theme.characters.hbar.to_string().repeat(4),
+        )?;
+        Ok(())
+    }
+
+    fn render_line_gutter(
+        &self,
+        f: &mut impl fmt::Write,
+        max_gutter: usize,
+        line: &Line,
+        highlights: &[FancySpan],
+    ) -> fmt::Result {
+        if max_gutter == 0 {
+            return Ok(());
+        }
+        let chars = &self.theme.characters;
+        let mut gutter = String::new();
+        let applicable = highlights.iter().filter(|hl| line.span_applies(hl));
+        let mut arrow = false;
+        for (i, hl) in applicable.enumerate() {
+            if line.span_starts(hl) {
+                gutter.push_str(&chars.ltop.style(hl.style).to_string());
+                gutter.push_str(
+                    &chars
+                        .hbar
+                        .to_string()
+                        .repeat(max_gutter.saturating_sub(i))
+                        .style(hl.style)
+                        .to_string(),
+                );
+                gutter.push_str(&chars.rarrow.style(hl.style).to_string());
+                arrow = true;
+                break;
+            } else if line.span_ends(hl) {
+                if hl.label().is_some() {
+                    gutter.push_str(&chars.lcross.style(hl.style).to_string());
+                } else {
+                    gutter.push_str(&chars.lbot.style(hl.style).to_string());
+                }
+                gutter.push_str(
+                    &chars
+                        .hbar
+                        .to_string()
+                        .repeat(max_gutter.saturating_sub(i))
+                        .style(hl.style)
+                        .to_string(),
+                );
+                gutter.push_str(&chars.rarrow.style(hl.style).to_string());
+                arrow = true;
+                break;
+            } else if line.span_flyby(hl) {
+                gutter.push_str(&chars.vbar.style(hl.style).to_string());
+            } else {
+                gutter.push(' ');
+            }
+        }
+        write!(
+            f,
+            "{}{}",
+            gutter,
+            " ".repeat(
+                if arrow { 1 } else { 3 } + max_gutter.saturating_sub(gutter.chars().count())
+            )
+        )?;
+        Ok(())
+    }
+
+    fn render_highlight_gutter(
+        &self,
+        f: &mut impl fmt::Write,
+        max_gutter: usize,
+        line: &Line,
+        highlights: &[FancySpan],
+    ) -> fmt::Result {
+        if max_gutter == 0 {
+            return Ok(());
+        }
+        let chars = &self.theme.characters;
+        let mut gutter = String::new();
+        let applicable = highlights.iter().filter(|hl| line.span_applies(hl));
+        for (i, hl) in applicable.enumerate() {
+            if !line.span_line_only(hl) && line.span_ends(hl) {
+                gutter.push_str(&chars.lbot.style(hl.style).to_string());
+                gutter.push_str(
+                    &chars
+                        .hbar
+                        .to_string()
+                        .repeat(max_gutter.saturating_sub(i) + 2)
+                        .style(hl.style)
+                        .to_string(),
+                );
+                break;
+            } else {
+                gutter.push_str(&chars.vbar.style(hl.style).to_string());
+            }
+        }
+        write!(f, "{:width$}", gutter, width = max_gutter + 1)?;
+        Ok(())
+    }
+
+    fn write_linum(&self, f: &mut impl fmt::Write, width: usize, linum: usize) -> fmt::Result {
+        write!(
+            f,
+            " {:width$} {} ",
+            linum.style(self.theme.styles.linum),
+            self.theme.characters.vbar,
+            width = width
+        )?;
+        Ok(())
+    }
+
+    fn write_no_linum(&self, f: &mut impl fmt::Write, width: usize) -> fmt::Result {
+        write!(
+            f,
+            " {:width$} {} ",
+            "",
+            self.theme.characters.vbar_break,
+            width = width
+        )?;
+        Ok(())
+    }
+
+    /// Returns an iterator over the visual width of each character in a line.
+    fn line_visual_char_width<'a>(&self, text: &'a str) -> impl Iterator<Item = usize> + 'a {
+        let mut column = 0;
+        let tab_width = self.tab_width;
+        text.chars().map(move |c| {
+            let width = if c == '\t' {
+                // Round up to the next multiple of tab_width
+                tab_width - column % tab_width
+            } else {
+                c.width().unwrap_or(0)
+            };
+            column += width;
+            width
+        })
+    }
+
+    /// Returns the visual column position of a byte offset on a specific line.
+    fn visual_offset(&self, line: &Line, offset: usize) -> usize {
+        let line_range = line.offset..=(line.offset + line.length);
+        assert!(line_range.contains(&offset));
+
+        let text_index = offset - line.offset;
+        let text = &line.text[..text_index.min(line.text.len())];
+        let text_width = self.line_visual_char_width(text).sum();
+        if text_index > line.text.len() {
+            // Spans extending past the end of the line are always rendered as
+            // one column past the end of the visible line.
+            //
+            // This doesn't necessarily correspond to a specific byte-offset,
+            // since a span extending past the end of the line could contain:
+            //  - an actual \n character (1 byte)
+            //  - a CRLF (2 bytes)
+            //  - EOF (0 bytes)
+            text_width + 1
+        } else {
+            text_width
+        }
+    }
+
+    /// Renders a line to the output formatter, replacing tabs with spaces.
+    fn render_line_text(&self, f: &mut impl fmt::Write, text: &str) -> fmt::Result {
+        for (c, width) in text.chars().zip(self.line_visual_char_width(text)) {
+            if c == '\t' {
+                for _ in 0..width {
+                    f.write_char(' ')?
+                }
+            } else {
+                f.write_char(c)?
+            }
+        }
+        f.write_char('\n')?;
+        Ok(())
+    }
+
+    fn render_single_line_highlights(
+        &self,
+        f: &mut impl fmt::Write,
+        line: &Line,
+        linum_width: usize,
+        max_gutter: usize,
+        single_liners: &[&FancySpan],
+        all_highlights: &[FancySpan],
+    ) -> fmt::Result {
+        let mut underlines = String::new();
+        let mut highest = 0;
+
+        let chars = &self.theme.characters;
+        let vbar_offsets: Vec<_> = single_liners
+            .iter()
+            .map(|hl| {
+                let byte_start = hl.offset();
+                let byte_end = hl.offset() + hl.len();
+                let start = self.visual_offset(line, byte_start).max(highest);
+                let end = self.visual_offset(line, byte_end).max(start + 1);
+
+                let vbar_offset = (start + end) / 2;
+                let num_left = vbar_offset - start;
+                let num_right = end - vbar_offset - 1;
+                if start < end {
+                    underlines.push_str(
+                        &format!(
+                            "{:width$}{}{}{}",
+                            "",
+                            chars.underline.to_string().repeat(num_left),
+                            if hl.len() == 0 {
+                                chars.uarrow
+                            } else if hl.label().is_some() {
+                                chars.underbar
+                            } else {
+                                chars.underline
+                            },
+                            chars.underline.to_string().repeat(num_right),
+                            width = start.saturating_sub(highest),
+                        )
+                        .style(hl.style)
+                        .to_string(),
+                    );
+                }
+                highest = std::cmp::max(highest, end);
+
+                (hl, vbar_offset)
+            })
+            .collect();
+        writeln!(f, "{}", underlines)?;
+
+        for hl in single_liners.iter().rev() {
+            if let Some(label) = hl.label() {
+                self.write_no_linum(f, linum_width)?;
+                self.render_highlight_gutter(f, max_gutter, line, all_highlights)?;
+                let mut curr_offset = 1usize;
+                for (offset_hl, vbar_offset) in &vbar_offsets {
+                    while curr_offset < *vbar_offset + 1 {
+                        write!(f, " ")?;
+                        curr_offset += 1;
+                    }
+                    if *offset_hl != hl {
+                        write!(f, "{}", chars.vbar.to_string().style(offset_hl.style))?;
+                        curr_offset += 1;
+                    } else {
+                        let lines = format!(
+                            "{}{} {}",
+                            chars.lbot,
+                            chars.hbar.to_string().repeat(2),
+                            label,
+                        );
+                        writeln!(f, "{}", lines.style(hl.style))?;
+                        break;
+                    }
+                }
+            }
+        }
+        Ok(())
+    }
+
+    fn render_multi_line_end(&self, f: &mut impl fmt::Write, hl: &FancySpan) -> fmt::Result {
+        writeln!(
+            f,
+            "{} {}",
+            self.theme.characters.hbar.style(hl.style),
+            hl.label().unwrap_or_else(|| "".into()),
+        )?;
+        Ok(())
+    }
+
+    fn get_lines<'a>(
+        &'a self,
+        source: &'a dyn SourceCode,
+        context_span: &'a SourceSpan,
+    ) -> Result<(Box<dyn SpanContents<'a> + 'a>, Vec<Line>), fmt::Error> {
+        let context_data = source
+            .read_span(context_span, self.context_lines, self.context_lines)
+            .map_err(|_| fmt::Error)?;
+        let context = std::str::from_utf8(context_data.data()).expect("Bad utf8 detected");
+        let mut line = context_data.line();
+        let mut column = context_data.column();
+        let mut offset = context_data.span().offset();
+        let mut line_offset = offset;
+        let mut iter = context.chars().peekable();
+        let mut line_str = String::new();
+        let mut lines = Vec::new();
+        while let Some(char) = iter.next() {
+            offset += char.len_utf8();
+            let mut at_end_of_file = false;
+            match char {
+                '\r' => {
+                    if iter.next_if_eq(&'\n').is_some() {
+                        offset += 1;
+                        line += 1;
+                        column = 0;
+                    } else {
+                        line_str.push(char);
+                        column += 1;
+                    }
+                    at_end_of_file = iter.peek().is_none();
+                }
+                '\n' => {
+                    at_end_of_file = iter.peek().is_none();
+                    line += 1;
+                    column = 0;
+                }
+                _ => {
+                    line_str.push(char);
+                    column += 1;
+                }
+            }
+
+            if iter.peek().is_none() && !at_end_of_file {
+                line += 1;
+            }
+
+            if column == 0 || iter.peek().is_none() {
+                lines.push(Line {
+                    line_number: line,
+                    offset: line_offset,
+                    length: offset - line_offset,
+                    text: line_str.clone(),
+                });
+                line_str.clear();
+                line_offset = offset;
+            }
+        }
+        Ok((context_data, lines))
+    }
+}
+
+impl ReportHandler for GraphicalReportHandler {
+    fn debug(&self, diagnostic: &(dyn Diagnostic), f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        if f.alternate() {
+            return fmt::Debug::fmt(diagnostic, f);
+        }
+
+        self.render_report(f, diagnostic)
+    }
+}
+
+/*
+Support types
+*/
+
+#[derive(Debug)]
+struct Line {
+    line_number: usize,
+    offset: usize,
+    length: usize,
+    text: String,
+}
+
+impl Line {
+    fn span_line_only(&self, span: &FancySpan) -> bool {
+        span.offset() >= self.offset && span.offset() + span.len() <= self.offset + self.length
+    }
+
+    fn span_applies(&self, span: &FancySpan) -> bool {
+        let spanlen = if span.len() == 0 { 1 } else { span.len() };
+        // Span starts in this line
+        (span.offset() >= self.offset && span.offset() < self.offset + self.length)
+        // Span passes through this line
+        || (span.offset() < self.offset && span.offset() + spanlen > self.offset + self.length) //todo
+        // Span ends on this line
+        || (span.offset() + spanlen > self.offset && span.offset() + spanlen <= self.offset + self.length)
+    }
+
+    // A 'flyby' is a multi-line span that technically covers this line, but
+    // does not begin or end within the line itself. This method is used to
+    // calculate gutters.
+    fn span_flyby(&self, span: &FancySpan) -> bool {
+        // The span itself starts before this line's starting offset (so, in a
+        // prev line).
+        span.offset() < self.offset
+            // ...and it stops after this line's end.
+            && span.offset() + span.len() > self.offset + self.length
+    }
+
+    // Does this line contain the *beginning* of this multiline span?
+    // This assumes self.span_applies() is true already.
+    fn span_starts(&self, span: &FancySpan) -> bool {
+        span.offset() >= self.offset
+    }
+
+    // Does this line contain the *end* of this multiline span?
+    // This assumes self.span_applies() is true already.
+    fn span_ends(&self, span: &FancySpan) -> bool {
+        span.offset() + span.len() >= self.offset
+            && span.offset() + span.len() <= self.offset + self.length
+    }
+}
+
+#[derive(Debug, Clone)]
+struct FancySpan {
+    label: Option<String>,
+    span: SourceSpan,
+    style: Style,
+}
+
+impl PartialEq for FancySpan {
+    fn eq(&self, other: &Self) -> bool {
+        self.label == other.label && self.span == other.span
+    }
+}
+
+impl FancySpan {
+    fn new(label: Option<String>, span: SourceSpan, style: Style) -> Self {
+        FancySpan { label, span, style }
+    }
+
+    fn style(&self) -> Style {
+        self.style
+    }
+
+    fn label(&self) -> Option<String> {
+        self.label
+            .as_ref()
+            .map(|l| l.style(self.style()).to_string())
+    }
+
+    fn offset(&self) -> usize {
+        self.span.offset()
+    }
+
+    fn len(&self) -> usize {
+        self.span.len()
+    }
+}
diff --git a/src/handlers/json.rs b/src/handlers/json.rs
new file mode 100644
index 0000000..29e21a0
--- /dev/null
+++ b/src/handlers/json.rs
@@ -0,0 +1,182 @@
+use std::fmt::{self, Write};
+
+use crate::{
+    diagnostic_chain::DiagnosticChain, protocol::Diagnostic, ReportHandler, Severity, SourceCode,
+};
+
+/**
+[`ReportHandler`] that renders JSON output. It's a machine-readable output.
+*/
+#[derive(Debug, Clone)]
+pub struct JSONReportHandler;
+
+impl JSONReportHandler {
+    /// Create a new [`JSONReportHandler`]. There are no customization
+    /// options.
+    pub const fn new() -> Self {
+        Self
+    }
+}
+
+impl Default for JSONReportHandler {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+struct Escape<'a>(&'a str);
+
+impl fmt::Display for Escape<'_> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        for c in self.0.chars() {
+            let escape = match c {
+                '\\' => Some(r"\\"),
+                '"' => Some(r#"\""#),
+                '\r' => Some(r"\r"),
+                '\n' => Some(r"\n"),
+                '\t' => Some(r"\t"),
+                '\u{08}' => Some(r"\b"),
+                '\u{0c}' => Some(r"\f"),
+                _ => None,
+            };
+            if let Some(escape) = escape {
+                f.write_str(escape)?;
+            } else {
+                f.write_char(c)?;
+            }
+        }
+        Ok(())
+    }
+}
+
+const fn escape(input: &'_ str) -> Escape<'_> {
+    Escape(input)
+}
+
+impl JSONReportHandler {
+    /// Render a [`Diagnostic`]. This function is mostly internal and meant to
+    /// be called by the toplevel [`ReportHandler`] handler, but is made public
+    /// to make it easier (possible) to test in isolation from global state.
+    pub fn render_report(
+        &self,
+        f: &mut impl fmt::Write,
+        diagnostic: &(dyn Diagnostic),
+    ) -> fmt::Result {
+        self._render_report(f, diagnostic, None)
+    }
+
+    fn _render_report(
+        &self,
+        f: &mut impl fmt::Write,
+        diagnostic: &(dyn Diagnostic),
+        parent_src: Option<&dyn SourceCode>,
+    ) -> fmt::Result {
+        write!(f, r#"{{"message": "{}","#, escape(&diagnostic.to_string()))?;
+        if let Some(code) = diagnostic.code() {
+            write!(f, r#""code": "{}","#, escape(&code.to_string()))?;
+        }
+        let severity = match diagnostic.severity() {
+            Some(Severity::Error) | None => "error",
+            Some(Severity::Warning) => "warning",
+            Some(Severity::Advice) => "advice",
+        };
+        write!(f, r#""severity": "{:}","#, severity)?;
+        if let Some(cause_iter) = diagnostic
+            .diagnostic_source()
+            .map(DiagnosticChain::from_diagnostic)
+            .or_else(|| diagnostic.source().map(DiagnosticChain::from_stderror))
+        {
+            write!(f, r#""causes": ["#)?;
+            let mut add_comma = false;
+            for error in cause_iter {
+                if add_comma {
+                    write!(f, ",")?;
+                } else {
+                    add_comma = true;
+                }
+                write!(f, r#""{}""#, escape(&error.to_string()))?;
+            }
+            write!(f, "],")?
+        } else {
+            write!(f, r#""causes": [],"#)?;
+        }
+        if let Some(url) = diagnostic.url() {
+            write!(f, r#""url": "{}","#, &url.to_string())?;
+        }
+        if let Some(help) = diagnostic.help() {
+            write!(f, r#""help": "{}","#, escape(&help.to_string()))?;
+        }
+        let src = diagnostic.source_code().or(parent_src);
+        if let Some(src) = src {
+            self.render_snippets(f, diagnostic, src)?;
+        }
+        if let Some(labels) = diagnostic.labels() {
+            write!(f, r#""labels": ["#)?;
+            let mut add_comma = false;
+            for label in labels {
+                if add_comma {
+                    write!(f, ",")?;
+                } else {
+                    add_comma = true;
+                }
+                write!(f, "{{")?;
+                if let Some(label_name) = label.label() {
+                    write!(f, r#""label": "{}","#, escape(label_name))?;
+                }
+                write!(f, r#""span": {{"#)?;
+                write!(f, r#""offset": {},"#, label.offset())?;
+                write!(f, r#""length": {}"#, label.len())?;
+
+                write!(f, "}}}}")?;
+            }
+            write!(f, "],")?;
+        } else {
+            write!(f, r#""labels": [],"#)?;
+        }
+        if let Some(relateds) = diagnostic.related() {
+            write!(f, r#""related": ["#)?;
+            let mut add_comma = false;
+            for related in relateds {
+                if add_comma {
+                    write!(f, ",")?;
+                } else {
+                    add_comma = true;
+                }
+                self._render_report(f, related, src)?;
+            }
+            write!(f, "]")?;
+        } else {
+            write!(f, r#""related": []"#)?;
+        }
+        write!(f, "}}")
+    }
+
+    fn render_snippets(
+        &self,
+        f: &mut impl fmt::Write,
+        diagnostic: &(dyn Diagnostic),
+        source: &dyn SourceCode,
+    ) -> fmt::Result {
+        if let Some(mut labels) = diagnostic.labels() {
+            if let Some(label) = labels.next() {
+                if let Ok(span_content) = source.read_span(label.inner(), 0, 0) {
+                    let filename = span_content.name().unwrap_or_default();
+                    return write!(f, r#""filename": "{}","#, escape(filename));
+                }
+            }
+        }
+        write!(f, r#""filename": "","#)
+    }
+}
+
+impl ReportHandler for JSONReportHandler {
+    fn debug(&self, diagnostic: &(dyn Diagnostic), f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.render_report(f, diagnostic)
+    }
+}
+
+#[test]
+fn test_escape() {
+    assert_eq!(escape("a\nb").to_string(), r"a\nb");
+    assert_eq!(escape("C:\\Miette").to_string(), r"C:\\Miette");
+}
diff --git a/src/handlers/mod.rs b/src/handlers/mod.rs
new file mode 100644
index 0000000..fde2dc9
--- /dev/null
+++ b/src/handlers/mod.rs
@@ -0,0 +1,24 @@
+/*!
+Reporters included with `miette`.
+*/
+
+#[allow(unreachable_pub)]
+pub use debug::*;
+#[allow(unreachable_pub)]
+#[cfg(feature = "fancy-no-backtrace")]
+pub use graphical::*;
+#[allow(unreachable_pub)]
+pub use json::*;
+#[allow(unreachable_pub)]
+pub use narratable::*;
+#[allow(unreachable_pub)]
+#[cfg(feature = "fancy-no-backtrace")]
+pub use theme::*;
+
+mod debug;
+#[cfg(feature = "fancy-no-backtrace")]
+mod graphical;
+mod json;
+mod narratable;
+#[cfg(feature = "fancy-no-backtrace")]
+mod theme;
diff --git a/src/handlers/narratable.rs b/src/handlers/narratable.rs
new file mode 100644
index 0000000..c809124
--- /dev/null
+++ b/src/handlers/narratable.rs
@@ -0,0 +1,423 @@
+use std::fmt;
+
+use unicode_width::{UnicodeWidthChar, UnicodeWidthStr};
+
+use crate::diagnostic_chain::DiagnosticChain;
+use crate::protocol::{Diagnostic, Severity};
+use crate::{LabeledSpan, MietteError, ReportHandler, SourceCode, SourceSpan, SpanContents};
+
+/**
+[`ReportHandler`] that renders plain text and avoids extraneous graphics.
+It's optimized for screen readers and braille users, but is also used in any
+non-graphical environments, such as non-TTY output.
+*/
+#[derive(Debug, Clone)]
+pub struct NarratableReportHandler {
+    context_lines: usize,
+    with_cause_chain: bool,
+    footer: Option<String>,
+}
+
+impl NarratableReportHandler {
+    /// Create a new [`NarratableReportHandler`]. There are no customization
+    /// options.
+    pub const fn new() -> Self {
+        Self {
+            footer: None,
+            context_lines: 1,
+            with_cause_chain: true,
+        }
+    }
+
+    /// Include the cause chain of the top-level error in the report, if
+    /// available.
+    pub const fn with_cause_chain(mut self) -> Self {
+        self.with_cause_chain = true;
+        self
+    }
+
+    /// Do not include the cause chain of the top-level error in the report.
+    pub const fn without_cause_chain(mut self) -> Self {
+        self.with_cause_chain = false;
+        self
+    }
+
+    /// Set the footer to be displayed at the end of the report.
+    pub fn with_footer(mut self, footer: String) -> Self {
+        self.footer = Some(footer);
+        self
+    }
+
+    /// Sets the number of lines of context to show around each error.
+    pub const fn with_context_lines(mut self, lines: usize) -> Self {
+        self.context_lines = lines;
+        self
+    }
+}
+
+impl Default for NarratableReportHandler {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl NarratableReportHandler {
+    /// Render a [`Diagnostic`]. This function is mostly internal and meant to
+    /// be called by the toplevel [`ReportHandler`] handler, but is
+    /// made public to make it easier (possible) to test in isolation from
+    /// global state.
+    pub fn render_report(
+        &self,
+        f: &mut impl fmt::Write,
+        diagnostic: &(dyn Diagnostic),
+    ) -> fmt::Result {
+        self.render_header(f, diagnostic)?;
+        if self.with_cause_chain {
+            self.render_causes(f, diagnostic)?;
+        }
+        let src = diagnostic.source_code();
+        self.render_snippets(f, diagnostic, src)?;
+        self.render_footer(f, diagnostic)?;
+        self.render_related(f, diagnostic, src)?;
+        if let Some(footer) = &self.footer {
+            writeln!(f, "{}", footer)?;
+        }
+        Ok(())
+    }
+
+    fn render_header(&self, f: &mut impl fmt::Write, diagnostic: &(dyn Diagnostic)) -> fmt::Result {
+        writeln!(f, "{}", diagnostic)?;
+        let severity = match diagnostic.severity() {
+            Some(Severity::Error) | None => "error",
+            Some(Severity::Warning) => "warning",
+            Some(Severity::Advice) => "advice",
+        };
+        writeln!(f, "    Diagnostic severity: {}", severity)?;
+        Ok(())
+    }
+
+    fn render_causes(&self, f: &mut impl fmt::Write, diagnostic: &(dyn Diagnostic)) -> fmt::Result {
+        if let Some(cause_iter) = diagnostic
+            .diagnostic_source()
+            .map(DiagnosticChain::from_diagnostic)
+            .or_else(|| diagnostic.source().map(DiagnosticChain::from_stderror))
+        {
+            for error in cause_iter {
+                writeln!(f, "    Caused by: {}", error)?;
+            }
+        }
+
+        Ok(())
+    }
+
+    fn render_footer(&self, f: &mut impl fmt::Write, diagnostic: &(dyn Diagnostic)) -> fmt::Result {
+        if let Some(help) = diagnostic.help() {
+            writeln!(f, "diagnostic help: {}", help)?;
+        }
+        if let Some(code) = diagnostic.code() {
+            writeln!(f, "diagnostic code: {}", code)?;
+        }
+        if let Some(url) = diagnostic.url() {
+            writeln!(f, "For more details, see:\n{}", url)?;
+        }
+        Ok(())
+    }
+
+    fn render_related(
+        &self,
+        f: &mut impl fmt::Write,
+        diagnostic: &(dyn Diagnostic),
+        parent_src: Option<&dyn SourceCode>,
+    ) -> fmt::Result {
+        if let Some(related) = diagnostic.related() {
+            writeln!(f)?;
+            for rel in related {
+                match rel.severity() {
+                    Some(Severity::Error) | None => write!(f, "Error: ")?,
+                    Some(Severity::Warning) => write!(f, "Warning: ")?,
+                    Some(Severity::Advice) => write!(f, "Advice: ")?,
+                };
+                self.render_header(f, rel)?;
+                writeln!(f)?;
+                self.render_causes(f, rel)?;
+                let src = rel.source_code().or(parent_src);
+                self.render_snippets(f, rel, src)?;
+                self.render_footer(f, rel)?;
+                self.render_related(f, rel, src)?;
+            }
+        }
+        Ok(())
+    }
+
+    fn render_snippets(
+        &self,
+        f: &mut impl fmt::Write,
+        diagnostic: &(dyn Diagnostic),
+        source_code: Option<&dyn SourceCode>,
+    ) -> fmt::Result {
+        if let Some(source) = source_code {
+            if let Some(labels) = diagnostic.labels() {
+                let mut labels = labels.collect::<Vec<_>>();
+                labels.sort_unstable_by_key(|l| l.inner().offset());
+                if !labels.is_empty() {
+                    let contents = labels
+                        .iter()
+                        .map(|label| {
+                            source.read_span(label.inner(), self.context_lines, self.context_lines)
+                        })
+                        .collect::<Result<Vec<Box<dyn SpanContents<'_>>>, MietteError>>()
+                        .map_err(|_| fmt::Error)?;
+                    let mut contexts = Vec::new();
+                    for (right, right_conts) in labels.iter().cloned().zip(contents.iter()) {
+                        if contexts.is_empty() {
+                            contexts.push((right, right_conts));
+                        } else {
+                            let (left, left_conts) = contexts.last().unwrap().clone();
+                            let left_end = left.offset() + left.len();
+                            let right_end = right.offset() + right.len();
+                            if left_conts.line() + left_conts.line_count() >= right_conts.line() {
+                                // The snippets will overlap, so we create one Big Chunky Boi
+                                let new_span = LabeledSpan::new(
+                                    left.label().map(String::from),
+                                    left.offset(),
+                                    if right_end >= left_end {
+                                        // Right end goes past left end
+                                        right_end - left.offset()
+                                    } else {
+                                        // right is contained inside left
+                                        left.len()
+                                    },
+                                );
+                                if source
+                                    .read_span(
+                                        new_span.inner(),
+                                        self.context_lines,
+                                        self.context_lines,
+                                    )
+                                    .is_ok()
+                                {
+                                    contexts.pop();
+                                    contexts.push((
+                                        new_span, // We'll throw this away later
+                                        left_conts,
+                                    ));
+                                } else {
+                                    contexts.push((right, right_conts));
+                                }
+                            } else {
+                                contexts.push((right, right_conts));
+                            }
+                        }
+                    }
+                    for (ctx, _) in contexts {
+                        self.render_context(f, source, &ctx, &labels[..])?;
+                    }
+                }
+            }
+        }
+        Ok(())
+    }
+
+    fn render_context(
+        &self,
+        f: &mut impl fmt::Write,
+        source: &dyn SourceCode,
+        context: &LabeledSpan,
+        labels: &[LabeledSpan],
+    ) -> fmt::Result {
+        let (contents, lines) = self.get_lines(source, context.inner())?;
+        write!(f, "Begin snippet")?;
+        if let Some(filename) = contents.name() {
+            write!(f, " for {}", filename,)?;
+        }
+        writeln!(
+            f,
+            " starting at line {}, column {}",
+            contents.line() + 1,
+            contents.column() + 1
+        )?;
+        writeln!(f)?;
+        for line in &lines {
+            writeln!(f, "snippet line {}: {}", line.line_number, line.text)?;
+            let relevant = labels
+                .iter()
+                .filter_map(|l| line.span_attach(l.inner()).map(|a| (a, l)));
+            for (attach, label) in relevant {
+                match attach {
+                    SpanAttach::Contained { col_start, col_end } if col_start == col_end => {
+                        write!(
+                            f,
+                            "    label at line {}, column {}",
+                            line.line_number, col_start,
+                        )?;
+                    }
+                    SpanAttach::Contained { col_start, col_end } => {
+                        write!(
+                            f,
+                            "    label at line {}, columns {} to {}",
+                            line.line_number, col_start, col_end,
+                        )?;
+                    }
+                    SpanAttach::Starts { col_start } => {
+                        write!(
+                            f,
+                            "    label starting at line {}, column {}",
+                            line.line_number, col_start,
+                        )?;
+                    }
+                    SpanAttach::Ends { col_end } => {
+                        write!(
+                            f,
+                            "    label ending at line {}, column {}",
+                            line.line_number, col_end,
+                        )?;
+                    }
+                }
+                if let Some(label) = label.label() {
+                    write!(f, ": {}", label)?;
+                }
+                writeln!(f)?;
+            }
+        }
+        Ok(())
+    }
+
+    fn get_lines<'a>(
+        &'a self,
+        source: &'a dyn SourceCode,
+        context_span: &'a SourceSpan,
+    ) -> Result<(Box<dyn SpanContents<'a> + 'a>, Vec<Line>), fmt::Error> {
+        let context_data = source
+            .read_span(context_span, self.context_lines, self.context_lines)
+            .map_err(|_| fmt::Error)?;
+        let context = std::str::from_utf8(context_data.data()).expect("Bad utf8 detected");
+        let mut line = context_data.line();
+        let mut column = context_data.column();
+        let mut offset = context_data.span().offset();
+        let mut line_offset = offset;
+        let mut iter = context.chars().peekable();
+        let mut line_str = String::new();
+        let mut lines = Vec::new();
+        while let Some(char) = iter.next() {
+            offset += char.len_utf8();
+            let mut at_end_of_file = false;
+            match char {
+                '\r' => {
+                    if iter.next_if_eq(&'\n').is_some() {
+                        offset += 1;
+                        line += 1;
+                        column = 0;
+                    } else {
+                        line_str.push(char);
+                        column += 1;
+                    }
+                    at_end_of_file = iter.peek().is_none();
+                }
+                '\n' => {
+                    at_end_of_file = iter.peek().is_none();
+                    line += 1;
+                    column = 0;
+                }
+                _ => {
+                    line_str.push(char);
+                    column += 1;
+                }
+            }
+
+            if iter.peek().is_none() && !at_end_of_file {
+                line += 1;
+            }
+
+            if column == 0 || iter.peek().is_none() {
+                lines.push(Line {
+                    line_number: line,
+                    offset: line_offset,
+                    text: line_str.clone(),
+                    at_end_of_file,
+                });
+                line_str.clear();
+                line_offset = offset;
+            }
+        }
+        Ok((context_data, lines))
+    }
+}
+
+impl ReportHandler for NarratableReportHandler {
+    fn debug(&self, diagnostic: &(dyn Diagnostic), f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        if f.alternate() {
+            return fmt::Debug::fmt(diagnostic, f);
+        }
+
+        self.render_report(f, diagnostic)
+    }
+}
+
+/*
+Support types
+*/
+
+struct Line {
+    line_number: usize,
+    offset: usize,
+    text: String,
+    at_end_of_file: bool,
+}
+
+enum SpanAttach {
+    Contained { col_start: usize, col_end: usize },
+    Starts { col_start: usize },
+    Ends { col_end: usize },
+}
+
+/// Returns column at offset, and nearest boundary if offset is in the middle of
+/// the character
+fn safe_get_column(text: &str, offset: usize, start: bool) -> usize {
+    let mut column = text.get(0..offset).map(|s| s.width()).unwrap_or_else(|| {
+        let mut column = 0;
+        for (idx, c) in text.char_indices() {
+            if offset <= idx {
+                break;
+            }
+            column += c.width().unwrap_or(0);
+        }
+        column
+    });
+    if start {
+        // Offset are zero-based, so plus one
+        column += 1;
+    } // On the other hand for end span, offset refers for the next column
+      // So we should do -1. column+1-1 == column
+    column
+}
+
+impl Line {
+    fn span_attach(&self, span: &SourceSpan) -> Option<SpanAttach> {
+        let span_end = span.offset() + span.len();
+        let line_end = self.offset + self.text.len();
+
+        let start_after = span.offset() >= self.offset;
+        let end_before = self.at_end_of_file || span_end <= line_end;
+
+        if start_after && end_before {
+            let col_start = safe_get_column(&self.text, span.offset() - self.offset, true);
+            let col_end = if span.is_empty() {
+                col_start
+            } else {
+                // span_end refers to the next character after token
+                // while col_end refers to the exact character, so -1
+                safe_get_column(&self.text, span_end - self.offset, false)
+            };
+            return Some(SpanAttach::Contained { col_start, col_end });
+        }
+        if start_after && span.offset() <= line_end {
+            let col_start = safe_get_column(&self.text, span.offset() - self.offset, true);
+            return Some(SpanAttach::Starts { col_start });
+        }
+        if end_before && span_end >= self.offset {
+            let col_end = safe_get_column(&self.text, span_end - self.offset, false);
+            return Some(SpanAttach::Ends { col_end });
+        }
+        None
+    }
+}
diff --git a/src/handlers/theme.rs b/src/handlers/theme.rs
new file mode 100644
index 0000000..1f5236a
--- /dev/null
+++ b/src/handlers/theme.rs
@@ -0,0 +1,275 @@
+use is_terminal::IsTerminal;
+use owo_colors::Style;
+
+/**
+Theme used by [`GraphicalReportHandler`](crate::GraphicalReportHandler) to
+render fancy [`Diagnostic`](crate::Diagnostic) reports.
+
+A theme consists of two things: the set of characters to be used for drawing,
+and the
+[`owo_colors::Style`](https://docs.rs/owo-colors/latest/owo_colors/struct.Style.html)s to be used to paint various items.
+
+You can create your own custom graphical theme using this type, or you can use
+one of the predefined ones using the methods below.
+*/
+#[derive(Debug, Clone)]
+pub struct GraphicalTheme {
+    /// Characters to be used for drawing.
+    pub characters: ThemeCharacters,
+    /// Styles to be used for painting.
+    pub styles: ThemeStyles,
+}
+
+impl GraphicalTheme {
+    /// ASCII-art-based graphical drawing, with ANSI styling.
+    pub fn ascii() -> Self {
+        Self {
+            characters: ThemeCharacters::ascii(),
+            styles: ThemeStyles::ansi(),
+        }
+    }
+
+    /// Graphical theme that draws using both ansi colors and unicode
+    /// characters.
+    ///
+    /// Note that full rgb colors aren't enabled by default because they're
+    /// an accessibility hazard, especially in the context of terminal themes
+    /// that can change the background color and make hardcoded colors illegible.
+    /// Such themes typically remap ansi codes properly, treating them more
+    /// like CSS classes than specific colors.
+    pub fn unicode() -> Self {
+        Self {
+            characters: ThemeCharacters::unicode(),
+            styles: ThemeStyles::ansi(),
+        }
+    }
+
+    /// Graphical theme that draws in monochrome, while still using unicode
+    /// characters.
+    pub fn unicode_nocolor() -> Self {
+        Self {
+            characters: ThemeCharacters::unicode(),
+            styles: ThemeStyles::none(),
+        }
+    }
+
+    /// A "basic" graphical theme that skips colors and unicode characters and
+    /// just does monochrome ascii art. If you want a completely non-graphical
+    /// rendering of your `Diagnostic`s, check out
+    /// [crate::NarratableReportHandler], or write your own
+    /// [crate::ReportHandler]!
+    pub fn none() -> Self {
+        Self {
+            characters: ThemeCharacters::ascii(),
+            styles: ThemeStyles::none(),
+        }
+    }
+}
+
+impl Default for GraphicalTheme {
+    fn default() -> Self {
+        match std::env::var("NO_COLOR") {
+            _ if !std::io::stdout().is_terminal() || !std::io::stderr().is_terminal() => {
+                Self::ascii()
+            }
+            Ok(string) if string != "0" => Self::unicode_nocolor(),
+            _ => Self::unicode(),
+        }
+    }
+}
+
+/**
+Styles for various parts of graphical rendering for the [crate::GraphicalReportHandler].
+*/
+#[derive(Debug, Clone)]
+pub struct ThemeStyles {
+    /// Style to apply to things highlighted as "error".
+    pub error: Style,
+    /// Style to apply to things highlighted as "warning".
+    pub warning: Style,
+    /// Style to apply to things highlighted as "advice".
+    pub advice: Style,
+    /// Style to apply to the help text.
+    pub help: Style,
+    /// Style to apply to filenames/links/URLs.
+    pub link: Style,
+    /// Style to apply to line numbers.
+    pub linum: Style,
+    /// Styles to cycle through (using `.iter().cycle()`), to render the lines
+    /// and text for diagnostic highlights.
+    pub highlights: Vec<Style>,
+}
+
+fn style() -> Style {
+    Style::new()
+}
+
+impl ThemeStyles {
+    /// Nice RGB colors.
+    /// [Credit](http://terminal.sexy/#FRUV0NDQFRUVrEFCkKlZ9L91ap-1qnWfdbWq0NDQUFBQrEFCkKlZ9L91ap-1qnWfdbWq9fX1).
+    pub fn rgb() -> Self {
+        Self {
+            error: style().fg_rgb::<255, 30, 30>(),
+            warning: style().fg_rgb::<244, 191, 117>(),
+            advice: style().fg_rgb::<106, 159, 181>(),
+            help: style().fg_rgb::<106, 159, 181>(),
+            link: style().fg_rgb::<92, 157, 255>().underline().bold(),
+            linum: style().dimmed(),
+            highlights: vec![
+                style().fg_rgb::<246, 87, 248>(),
+                style().fg_rgb::<30, 201, 212>(),
+                style().fg_rgb::<145, 246, 111>(),
+            ],
+        }
+    }
+
+    /// ANSI color-based styles.
+    pub fn ansi() -> Self {
+        Self {
+            error: style().red(),
+            warning: style().yellow(),
+            advice: style().cyan(),
+            help: style().cyan(),
+            link: style().cyan().underline().bold(),
+            linum: style().dimmed(),
+            highlights: vec![
+                style().magenta().bold(),
+                style().yellow().bold(),
+                style().green().bold(),
+            ],
+        }
+    }
+
+    /// No styling. Just regular ol' monochrome.
+    pub fn none() -> Self {
+        Self {
+            error: style(),
+            warning: style(),
+            advice: style(),
+            help: style(),
+            link: style(),
+            linum: style(),
+            highlights: vec![style()],
+        }
+    }
+}
+
+// ----------------------------------------
+// Most of these characters were taken from
+// https://github.com/zesterer/ariadne/blob/e3cb394cb56ecda116a0a1caecd385a49e7f6662/src/draw.rs
+
+/// Characters to be used when drawing when using
+/// [crate::GraphicalReportHandler].
+#[allow(missing_docs)]
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct ThemeCharacters {
+    pub hbar: char,
+    pub vbar: char,
+    pub xbar: char,
+    pub vbar_break: char,
+
+    pub uarrow: char,
+    pub rarrow: char,
+
+    pub ltop: char,
+    pub mtop: char,
+    pub rtop: char,
+    pub lbot: char,
+    pub rbot: char,
+    pub mbot: char,
+
+    pub lbox: char,
+    pub rbox: char,
+
+    pub lcross: char,
+    pub rcross: char,
+
+    pub underbar: char,
+    pub underline: char,
+
+    pub error: String,
+    pub warning: String,
+    pub advice: String,
+}
+
+impl ThemeCharacters {
+    /// Fancy unicode-based graphical elements.
+    pub fn unicode() -> Self {
+        Self {
+            hbar: '─',
+            vbar: '│',
+            xbar: '┼',
+            vbar_break: '·',
+            uarrow: '▲',
+            rarrow: '▶',
+            ltop: '╭',
+            mtop: '┬',
+            rtop: '╮',
+            lbot: '╰',
+            mbot: '┴',
+            rbot: '╯',
+            lbox: '[',
+            rbox: ']',
+            lcross: '├',
+            rcross: '┤',
+            underbar: '┬',
+            underline: '─',
+            error: "×".into(),
+            warning: "⚠".into(),
+            advice: "☞".into(),
+        }
+    }
+
+    /// Emoji-heavy unicode characters.
+    pub fn emoji() -> Self {
+        Self {
+            hbar: '─',
+            vbar: '│',
+            xbar: '┼',
+            vbar_break: '·',
+            uarrow: '▲',
+            rarrow: '▶',
+            ltop: '╭',
+            mtop: '┬',
+            rtop: '╮',
+            lbot: '╰',
+            mbot: '┴',
+            rbot: '╯',
+            lbox: '[',
+            rbox: ']',
+            lcross: '├',
+            rcross: '┤',
+            underbar: '┬',
+            underline: '─',
+            error: "💥".into(),
+            warning: "⚠️".into(),
+            advice: "💡".into(),
+        }
+    }
+    /// ASCII-art-based graphical elements. Works well on older terminals.
+    pub fn ascii() -> Self {
+        Self {
+            hbar: '-',
+            vbar: '|',
+            xbar: '+',
+            vbar_break: ':',
+            uarrow: '^',
+            rarrow: '>',
+            ltop: ',',
+            mtop: 'v',
+            rtop: '.',
+            lbot: '`',
+            mbot: '^',
+            rbot: '\'',
+            lbox: '[',
+            rbox: ']',
+            lcross: '|',
+            rcross: '|',
+            underbar: '|',
+            underline: '^',
+            error: "x".into(),
+            warning: "!".into(),
+            advice: ">".into(),
+        }
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..cc113ce
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,670 @@
+#![deny(missing_docs, missing_debug_implementations, nonstandard_style)]
+#![warn(unreachable_pub, rust_2018_idioms)]
+//! You run miette? You run her code like the software? Oh. Oh! Error code for
+//! coder! Error code for One Thousand Lines!
+//!
+//! ## About
+//!
+//! `miette` is a diagnostic library for Rust. It includes a series of
+//! traits/protocols that allow you to hook into its error reporting facilities,
+//! and even write your own error reports! It lets you define error types that
+//! can print out like this (or in any format you like!):
+//!
+//! <img src="https://raw.githubusercontent.com/zkat/miette/main/images/serde_json.png" alt="Hi! miette also includes a screen-reader-oriented diagnostic printer that's enabled in various situations, such as when you use NO_COLOR or CLICOLOR settings, or on CI. This behavior is also fully configurable and customizable. For example, this is what this particular diagnostic will look like when the narrated printer is enabled:
+//! \
+//! Error: Received some bad JSON from the source. Unable to parse.
+//!     Caused by: missing field `foo` at line 1 column 1700
+//! \
+//! Begin snippet for https://api.nuget.org/v3/registration5-gz-semver2/json.net/index.json starting
+//! at line 1, column 1659
+//! \
+//! snippet line 1: gs&quot;:[&quot;json&quot;],&quot;title&quot;:&quot;&quot;,&quot;version&quot;:&quot;1.0.0&quot;},&quot;packageContent&quot;:&quot;https://api.nuget.o
+//!     highlight starting at line 1, column 1699: last parsing location
+//! \
+//! diagnostic help: This is a bug. It might be in ruget, or it might be in the
+//! source you're using, but it's definitely a bug and should be reported.
+//! diagnostic error code: ruget::api::bad_json
+//! " />
+//!
+//! > **NOTE: You must enable the `"fancy"` crate feature to get fancy report
+//! output like in the screenshots above.** You should only do this in your
+//! toplevel crate, as the fancy feature pulls in a number of dependencies that
+//! libraries and such might not want.
+//!
+//! ## Table of Contents <!-- omit in toc -->
+//!
+//! - [About](#about)
+//! - [Features](#features)
+//! - [Installing](#installing)
+//! - [Example](#example)
+//! - [Using](#using)
+//!   - [... in libraries](#-in-libraries)
+//!   - [... in application code](#-in-application-code)
+//!   - [... in `main()`](#-in-main)
+//!   - [... diagnostic code URLs](#-diagnostic-code-urls)
+//!   - [... snippets](#-snippets)
+//!   - [... multiple related errors](#-multiple-related-errors)
+//!   - [... delayed source code](#-delayed-source-code)
+//!   - [... handler options](#-handler-options)
+//!   - [... dynamic diagnostics](#-dynamic-diagnostics)
+//! - [Acknowledgements](#acknowledgements)
+//! - [License](#license)
+//!
+//! ## Features
+//!
+//! - Generic [`Diagnostic`] protocol, compatible (and dependent on)
+//!   [`std::error::Error`].
+//! - Unique error codes on every [`Diagnostic`].
+//! - Custom links to get more details on error codes.
+//! - Super handy derive macro for defining diagnostic metadata.
+//! - Replacements for [`anyhow`](https://docs.rs/anyhow)/[`eyre`](https://docs.rs/eyre)
+//!   types [`Result`], [`Report`] and the [`miette!`] macro for the
+//!   `anyhow!`/`eyre!` macros.
+//! - Generic support for arbitrary [`SourceCode`]s for snippet data, with
+//!   default support for `String`s included.
+//!
+//! The `miette` crate also comes bundled with a default [`ReportHandler`] with
+//! the following features:
+//!
+//! - Fancy graphical [diagnostic output](#about), using ANSI/Unicode text
+//! - single- and multi-line highlighting support
+//! - Screen reader/braille support, gated on [`NO_COLOR`](http://no-color.org/),
+//!   and other heuristics.
+//! - Fully customizable graphical theming (or overriding the printers
+//!   entirely).
+//! - Cause chain printing
+//! - Turns diagnostic codes into links in [supported terminals](https://gist.github.com/egmontkob/eb114294efbcd5adb1944c9f3cb5feda).
+//!
+//! ## Installing
+//!
+//! ```sh
+//! $ cargo add miette
+//! ```
+//!
+//! If you want to use the fancy printer in all these screenshots:
+//!
+//! ```sh
+//! $ cargo add miette --features fancy
+//! ```
+//!
+//! ## Example
+//!
+//! ```rust
+//! /*
+//! You can derive a `Diagnostic` from any `std::error::Error` type.
+//!
+//! `thiserror` is a great way to define them, and plays nicely with `miette`!
+//! */
+//! use miette::{Diagnostic, SourceSpan};
+//! use thiserror::Error;
+//!
+//! #[derive(Error, Debug, Diagnostic)]
+//! #[error("oops!")]
+//! #[diagnostic(
+//!     code(oops::my::bad),
+//!     url(docsrs),
+//!     help("try doing it better next time?")
+//! )]
+//! struct MyBad {
+//!     // The Source that we're gonna be printing snippets out of.
+//!     // This can be a String if you don't have or care about file names.
+//!     #[source_code]
+//!     src: NamedSource,
+//!     // Snippets and highlights can be included in the diagnostic!
+//!     #[label("This bit here")]
+//!     bad_bit: SourceSpan,
+//! }
+//!
+//! /*
+//! Now let's define a function!
+//!
+//! Use this `Result` type (or its expanded version) as the return type
+//! throughout your app (but NOT your libraries! Those should always return
+//! concrete types!).
+//! */
+//! use miette::{NamedSource, Result};
+//! fn this_fails() -> Result<()> {
+//!     // You can use plain strings as a `Source`, or anything that implements
+//!     // the one-method `Source` trait.
+//!     let src = "source\n  text\n    here".to_string();
+//!     let len = src.len();
+//!
+//!     Err(MyBad {
+//!         src: NamedSource::new("bad_file.rs", src),
+//!         bad_bit: (9, 4).into(),
+//!     })?;
+//!
+//!     Ok(())
+//! }
+//!
+//! /*
+//! Now to get everything printed nicely, just return a `Result<()>`
+//! and you're all set!
+//!
+//! Note: You can swap out the default reporter for a custom one using
+//! `miette::set_hook()`
+//! */
+//! fn pretend_this_is_main() -> Result<()> {
+//!     // kaboom~
+//!     this_fails()?;
+//!
+//!     Ok(())
+//! }
+//! ```
+//!
+//! And this is the output you'll get if you run this program:
+//!
+//! <img src="https://raw.githubusercontent.com/zkat/miette/main/images/single-line-example.png" alt="
+//! Narratable printout:
+//! \
+//! Error: Types mismatched for operation.
+//!     Diagnostic severity: error
+//! Begin snippet starting at line 1, column 1
+//! \
+//! snippet line 1: 3 + &quot;5&quot;
+//!     label starting at line 1, column 1: int
+//!     label starting at line 1, column 1: doesn't support these values.
+//!     label starting at line 1, column 1: string
+//! diagnostic help: Change int or string to be the right types and try again.
+//! diagnostic code: nu::parser::unsupported_operation
+//! For more details, see https://docs.rs/nu-parser/0.1.0/nu-parser/enum.ParseError.html#variant.UnsupportedOperation">
+//!
+//! ## Using
+//!
+//! ### ... in libraries
+//!
+//! `miette` is _fully compatible_ with library usage. Consumers who don't know
+//! about, or don't want, `miette` features can safely use its error types as
+//! regular [`std::error::Error`].
+//!
+//! We highly recommend using something like [`thiserror`](https://docs.rs/thiserror)
+//! to define unique error types and error wrappers for your library.
+//!
+//! While `miette` integrates smoothly with `thiserror`, it is _not required_.
+//! If you don't want to use the [`Diagnostic`] derive macro, you can implement
+//! the trait directly, just like with `std::error::Error`.
+//!
+//! ```rust
+//! // lib/error.rs
+//! use miette::Diagnostic;
+//! use thiserror::Error;
+//!
+//! #[derive(Error, Diagnostic, Debug)]
+//! pub enum MyLibError {
+//!     #[error(transparent)]
+//!     #[diagnostic(code(my_lib::io_error))]
+//!     IoError(#[from] std::io::Error),
+//!
+//!     #[error("Oops it blew up")]
+//!     #[diagnostic(code(my_lib::bad_code))]
+//!     BadThingHappened,
+//! }
+//! ```
+//!
+//! Then, return this error type from all your fallible public APIs. It's a best
+//! practice to wrap any "external" error types in your error `enum` instead of
+//! using something like [`Report`] in a library.
+//!
+//! ### ... in application code
+//!
+//! Application code tends to work a little differently than libraries. You
+//! don't always need or care to define dedicated error wrappers for errors
+//! coming from external libraries and tools.
+//!
+//! For this situation, `miette` includes two tools: [`Report`] and
+//! [`IntoDiagnostic`]. They work in tandem to make it easy to convert regular
+//! `std::error::Error`s into [`Diagnostic`]s. Additionally, there's a
+//! [`Result`] type alias that you can use to be more terse.
+//!
+//! When dealing with non-`Diagnostic` types, you'll want to
+//! `.into_diagnostic()` them:
+//!
+//! ```rust
+//! // my_app/lib/my_internal_file.rs
+//! use miette::{IntoDiagnostic, Result};
+//! use semver::Version;
+//!
+//! pub fn some_tool() -> Result<Version> {
+//!     Ok("1.2.x".parse().into_diagnostic()?)
+//! }
+//! ```
+//!
+//! `miette` also includes an `anyhow`/`eyre`-style `Context`/`WrapErr` traits
+//! that you can import to add ad-hoc context messages to your `Diagnostic`s, as
+//! well, though you'll still need to use `.into_diagnostic()` to make use of
+//! it:
+//!
+//! ```rust
+//! // my_app/lib/my_internal_file.rs
+//! use miette::{IntoDiagnostic, Result, WrapErr};
+//! use semver::Version;
+//!
+//! pub fn some_tool() -> Result<Version> {
+//!     Ok("1.2.x"
+//!         .parse()
+//!         .into_diagnostic()
+//!         .wrap_err("Parsing this tool's semver version failed.")?)
+//! }
+//! ```
+//!
+//! To construct your own simple adhoc error use the [miette!] macro:
+//! ```rust
+//! // my_app/lib/my_internal_file.rs
+//! use miette::{miette, IntoDiagnostic, Result, WrapErr};
+//! use semver::Version;
+//!
+//! pub fn some_tool() -> Result<Version> {
+//!     let version = "1.2.x";
+//!     Ok(version
+//!         .parse()
+//!         .map_err(|_| miette!("Invalid version {}", version))?)
+//! }
+//! ```
+//! There are also similar [bail!] and [ensure!] macros.
+//!
+//! ### ... in `main()`
+//!
+//! `main()` is just like any other part of your application-internal code. Use
+//! `Result` as your return value, and it will pretty-print your diagnostics
+//! automatically.
+//!
+//! > **NOTE:** You must enable the `"fancy"` crate feature to get fancy report
+//! output like in the screenshots here.** You should only do this in your
+//! toplevel crate, as the fancy feature pulls in a number of dependencies that
+//! libraries and such might not want.
+//!
+//! ```rust
+//! use miette::{IntoDiagnostic, Result};
+//! use semver::Version;
+//!
+//! fn pretend_this_is_main() -> Result<()> {
+//!     let version: Version = "1.2.x".parse().into_diagnostic()?;
+//!     println!("{}", version);
+//!     Ok(())
+//! }
+//! ```
+//!
+//! Please note: in order to get fancy diagnostic rendering with all the pretty
+//! colors and arrows, you should install `miette` with the `fancy` feature
+//! enabled:
+//!
+//! ```toml
+//! miette = { version = "X.Y.Z", features = ["fancy"] }
+//! ```
+//!
+//! ### ... diagnostic code URLs
+//!
+//! `miette` supports providing a URL for individual diagnostics. This URL will
+//! be displayed as an actual link in supported terminals, like so:
+//!
+//! <img
+//! src="https://raw.githubusercontent.com/zkat/miette/main/images/code_linking.png"
+//! alt=" Example showing the graphical report printer for miette
+//! pretty-printing an error code. The code is underlined and followed by text
+//! saying to 'click here'. A hover tooltip shows a full-fledged URL that can be
+//! Ctrl+Clicked to open in a browser.
+//! \
+//! This feature is also available in the narratable printer. It will add a line
+//! after printing the error code showing a plain URL that you can visit.
+//! ">
+//!
+//! To use this, you can add a `url()` sub-param to your `#[diagnostic]`
+//! attribute:
+//!
+//! ```rust
+//! use miette::Diagnostic;
+//! use thiserror::Error;
+//!
+//! #[derive(Error, Diagnostic, Debug)]
+//! #[error("kaboom")]
+//! #[diagnostic(
+//!     code(my_app::my_error),
+//!     // You can do formatting!
+//!     url("https://my_website.com/error_codes#{}", self.code().unwrap())
+//! )]
+//! struct MyErr;
+//! ```
+//!
+//! Additionally, if you're developing a library and your error type is exported
+//! from your crate's top level, you can use a special `url(docsrs)` option
+//! instead of manually constructing the URL. This will automatically create a
+//! link to this diagnostic on `docs.rs`, so folks can just go straight to your
+//! (very high quality and detailed!) documentation on this diagnostic:
+//!
+//! ```rust
+//! use miette::Diagnostic;
+//! use thiserror::Error;
+//!
+//! #[derive(Error, Diagnostic, Debug)]
+//! #[diagnostic(
+//!     code(my_app::my_error),
+//!     // Will link users to https://docs.rs/my_crate/0.0.0/my_crate/struct.MyErr.html
+//!     url(docsrs)
+//! )]
+//! #[error("kaboom")]
+//! struct MyErr;
+//! ```
+//!
+//! ### ... snippets
+//!
+//! Along with its general error handling and reporting features, `miette` also
+//! includes facilities for adding error spans/annotations/labels to your
+//! output. This can be very useful when an error is syntax-related, but you can
+//! even use it to print out sections of your own source code!
+//!
+//! To achieve this, `miette` defines its own lightweight [`SourceSpan`] type.
+//! This is a basic byte-offset and length into an associated [`SourceCode`]
+//! and, along with the latter, gives `miette` all the information it needs to
+//! pretty-print some snippets! You can also use your own `Into<SourceSpan>`
+//! types as label spans.
+//!
+//! The easiest way to define errors like this is to use the
+//! `derive(Diagnostic)` macro:
+//!
+//! ```rust
+//! use miette::{Diagnostic, SourceSpan};
+//! use thiserror::Error;
+//!
+//! #[derive(Diagnostic, Debug, Error)]
+//! #[error("oops")]
+//! #[diagnostic(code(my_lib::random_error))]
+//! pub struct MyErrorType {
+//!     // The `Source` that miette will use.
+//!     #[source_code]
+//!     src: String,
+//!
+//!     // This will underline/mark the specific code inside the larger
+//!     // snippet context.
+//!     #[label = "This is the highlight"]
+//!     err_span: SourceSpan,
+//!
+//!     // You can add as many labels as you want.
+//!     // They'll be rendered sequentially.
+//!     #[label("This is bad")]
+//!     snip2: (usize, usize), // `(usize, usize)` is `Into<SourceSpan>`!
+//!
+//!     // Snippets can be optional, by using Option:
+//!     #[label("some text")]
+//!     snip3: Option<SourceSpan>,
+//!
+//!     // with or without label text
+//!     #[label]
+//!     snip4: Option<SourceSpan>,
+//! }
+//! ```
+//!
+//! #### ... help text
+//! `miette` provides two facilities for supplying help text for your errors:
+//!
+//! The first is the `#[help()]` format attribute that applies to structs or
+//! enum variants:
+//!
+//! ```rust
+//! use miette::Diagnostic;
+//! use thiserror::Error;
+//!
+//! #[derive(Debug, Diagnostic, Error)]
+//! #[error("welp")]
+//! #[diagnostic(help("try doing this instead"))]
+//! struct Foo;
+//! ```
+//!
+//! The other is by programmatically supplying the help text as a field to
+//! your diagnostic:
+//!
+//! ```rust
+//! use miette::Diagnostic;
+//! use thiserror::Error;
+//!
+//! #[derive(Debug, Diagnostic, Error)]
+//! #[error("welp")]
+//! #[diagnostic()]
+//! struct Foo {
+//!     #[help]
+//!     advice: Option<String>, // Can also just be `String`
+//! }
+//!
+//! let err = Foo {
+//!     advice: Some("try doing this instead".to_string()),
+//! };
+//! ```
+//!
+//! ### ... multiple related errors
+//!
+//! `miette` supports collecting multiple errors into a single diagnostic, and
+//! printing them all together nicely.
+//!
+//! To do so, use the `#[related]` tag on any `IntoIter` field in your
+//! `Diagnostic` type:
+//!
+//! ```rust
+//! use miette::Diagnostic;
+//! use thiserror::Error;
+//!
+//! #[derive(Debug, Error, Diagnostic)]
+//! #[error("oops")]
+//! struct MyError {
+//!     #[related]
+//!     others: Vec<MyError>,
+//! }
+//! ```
+//!
+//! ### ... delayed source code
+//!
+//! Sometimes it makes sense to add source code to the error message later.
+//! One option is to use [`with_source_code()`](Report::with_source_code)
+//! method for that:
+//!
+//! ```rust,no_run
+//! use miette::{Diagnostic, SourceSpan};
+//! use thiserror::Error;
+//!
+//! #[derive(Diagnostic, Debug, Error)]
+//! #[error("oops")]
+//! #[diagnostic()]
+//! pub struct MyErrorType {
+//!     // Note: label but no source code
+//!     #[label]
+//!     err_span: SourceSpan,
+//! }
+//!
+//! fn do_something() -> miette::Result<()> {
+//!     // This function emits actual error with label
+//!     return Err(MyErrorType {
+//!         err_span: (7..11).into(),
+//!     })?;
+//! }
+//!
+//! fn main() -> miette::Result<()> {
+//!     do_something().map_err(|error| {
+//!         // And this code provides the source code for inner error
+//!         error.with_source_code(String::from("source code"))
+//!     })
+//! }
+//! ```
+//!
+//! Also source code can be provided by a wrapper type. This is especially
+//! useful in combination with `related`, when multiple errors should be
+//! emitted at the same time:
+//!
+//! ```rust,no_run
+//! use miette::{Diagnostic, Report, SourceSpan};
+//! use thiserror::Error;
+//!
+//! #[derive(Diagnostic, Debug, Error)]
+//! #[error("oops")]
+//! #[diagnostic()]
+//! pub struct InnerError {
+//!     // Note: label but no source code
+//!     #[label]
+//!     err_span: SourceSpan,
+//! }
+//!
+//! #[derive(Diagnostic, Debug, Error)]
+//! #[error("oops: multiple errors")]
+//! #[diagnostic()]
+//! pub struct MultiError {
+//!     // Note source code by no labels
+//!     #[source_code]
+//!     source_code: String,
+//!     // The source code above is used for these errors
+//!     #[related]
+//!     related: Vec<InnerError>,
+//! }
+//!
+//! fn do_something() -> Result<(), Vec<InnerError>> {
+//!     Err(vec![
+//!         InnerError {
+//!             err_span: (0..6).into(),
+//!         },
+//!         InnerError {
+//!             err_span: (7..11).into(),
+//!         },
+//!     ])
+//! }
+//!
+//! fn main() -> miette::Result<()> {
+//!     do_something().map_err(|err_list| MultiError {
+//!         source_code: "source code".into(),
+//!         related: err_list,
+//!     })?;
+//!     Ok(())
+//! }
+//! ```
+//!
+//! ### ... Diagnostic-based error sources.
+//!
+//! When one uses the `#[source]` attribute on a field, that usually comes
+//! from `thiserror`, and implements a method for
+//! [`std::error::Error::source`]. This works in many cases, but it's lossy:
+//! if the source of the diagnostic is a diagnostic itself, the source will
+//! simply be treated as an `std::error::Error`.
+//!
+//! While this has no effect on the existing _reporters_, since they don't use
+//! that information right now, APIs who might want this information will have
+//! no access to it.
+//!
+//! If it's important for you for this information to be available to users,
+//! you can use `#[diagnostic_source]` alongside `#[source]`. Not that you
+//! will likely want to use _both_:
+//!
+//! ```rust
+//! use miette::Diagnostic;
+//! use thiserror::Error;
+//!
+//! #[derive(Debug, Diagnostic, Error)]
+//! #[error("MyError")]
+//! struct MyError {
+//!     #[source]
+//!     #[diagnostic_source]
+//!     the_cause: OtherError,
+//! }
+//!
+//! #[derive(Debug, Diagnostic, Error)]
+//! #[error("OtherError")]
+//! struct OtherError;
+//! ```
+//!
+//! ### ... handler options
+//!
+//! [`MietteHandler`] is the default handler, and is very customizable. In
+//! most cases, you can simply use [`MietteHandlerOpts`] to tweak its behavior
+//! instead of falling back to your own custom handler.
+//!
+//! Usage is like so:
+//!
+//! ```rust,ignore
+//! miette::set_hook(Box::new(|_| {
+//!     Box::new(
+//!         miette::MietteHandlerOpts::new()
+//!             .terminal_links(true)
+//!             .unicode(false)
+//!             .context_lines(3)
+//!             .tab_width(4)
+//!             .build(),
+//!     )
+//! }))
+//!
+//! # .unwrap()
+//! ```
+//!
+//! See the docs for [`MietteHandlerOpts`] for more details on what you can
+//! customize!
+//!
+//! ### ... dynamic diagnostics
+//!
+//! If you...
+//! - ...don't know all the possible errors upfront
+//! - ...need to serialize/deserialize errors
+//! then you may want to use [`miette!`], [`diagnostic!`] macros or
+//! [`MietteDiagnostic`] directly to create diagnostic on the fly.
+//!
+//! ```rust,ignore
+//! # use miette::{miette, LabeledSpan, Report};
+//!
+//! let source = "2 + 2 * 2 = 8".to_string();
+//! let report = miette!(
+//!   labels = vec[
+//!       LabeledSpan::at(12..13, "this should be 6"),
+//!   ],
+//!   help = "'*' has greater precedence than '+'",
+//!   "Wrong answer"
+//! ).with_source_code(source);
+//! println!("{:?}", report)
+//! ```
+//!
+//! ## Acknowledgements
+//!
+//! `miette` was not developed in a void. It owes enormous credit to various
+//! other projects and their authors:
+//!
+//! - [`anyhow`](http://crates.io/crates/anyhow) and [`color-eyre`](https://crates.io/crates/color-eyre):
+//!   these two enormously influential error handling libraries have pushed
+//!   forward the experience of application-level error handling and error
+//!   reporting. `miette`'s `Report` type is an attempt at a very very rough
+//!   version of their `Report` types.
+//! - [`thiserror`](https://crates.io/crates/thiserror) for setting the standard
+//!   for library-level error definitions, and for being the inspiration behind
+//!   `miette`'s derive macro.
+//! - `rustc` and [@estebank](https://github.com/estebank) for their
+//!   state-of-the-art work in compiler diagnostics.
+//! - [`ariadne`](https://crates.io/crates/ariadne) for pushing forward how
+//!   _pretty_ these diagnostics can really look!
+//!
+//! ## License
+//!
+//! `miette` is released to the Rust community under the [Apache license
+//! 2.0](./LICENSE).
+//!
+//! It also includes code taken from [`eyre`](https://github.com/yaahc/eyre),
+//! and some from [`thiserror`](https://github.com/dtolnay/thiserror), also
+//! under the Apache License. Some code is taken from
+//! [`ariadne`](https://github.com/zesterer/ariadne), which is MIT licensed.
+pub use miette_derive::*;
+
+pub use error::*;
+pub use eyreish::*;
+#[cfg(feature = "fancy-no-backtrace")]
+pub use handler::*;
+pub use handlers::*;
+pub use miette_diagnostic::*;
+pub use named_source::*;
+#[cfg(feature = "fancy")]
+pub use panic::*;
+pub use protocol::*;
+
+mod chain;
+mod diagnostic_chain;
+mod error;
+mod eyreish;
+#[cfg(feature = "fancy-no-backtrace")]
+mod handler;
+mod handlers;
+#[doc(hidden)]
+pub mod macro_helpers;
+mod miette_diagnostic;
+mod named_source;
+#[cfg(feature = "fancy")]
+mod panic;
+mod protocol;
+mod source_impls;
diff --git a/src/macro_helpers.rs b/src/macro_helpers.rs
new file mode 100644
index 0000000..5520899
--- /dev/null
+++ b/src/macro_helpers.rs
@@ -0,0 +1,38 @@
+// Huge thanks to @jam1gamer for this hack:
+// https://twitter.com/jam1garner/status/1515887996444323840
+
+#[doc(hidden)]
+pub trait IsOption {}
+impl<T> IsOption for Option<T> {}
+
+#[doc(hidden)]
+#[derive(Debug, Default)]
+pub struct OptionalWrapper<T>(pub core::marker::PhantomData<T>);
+
+impl<T> OptionalWrapper<T> {
+    pub fn new() -> Self {
+        Self(core::marker::PhantomData)
+    }
+}
+
+#[doc(hidden)]
+pub trait ToOption {
+    #[doc(hidden)]
+    fn to_option<T>(self, value: T) -> Option<T>;
+}
+
+impl<T> OptionalWrapper<T>
+where
+    T: IsOption,
+{
+    #[doc(hidden)]
+    pub fn to_option(self, value: &T) -> &T {
+        value
+    }
+}
+
+impl<T> ToOption for &OptionalWrapper<T> {
+    fn to_option<U>(self, value: U) -> Option<U> {
+        Some(value)
+    }
+}
diff --git a/src/miette_diagnostic.rs b/src/miette_diagnostic.rs
new file mode 100644
index 0000000..67b75d0
--- /dev/null
+++ b/src/miette_diagnostic.rs
@@ -0,0 +1,365 @@
+use std::{
+    error::Error,
+    fmt::{Debug, Display},
+};
+
+#[cfg(feature = "serde")]
+use serde::{Deserialize, Serialize};
+
+use crate::{Diagnostic, LabeledSpan, Severity};
+
+/// Diagnostic that can be created at runtime.
+#[derive(Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+pub struct MietteDiagnostic {
+    /// Displayed diagnostic message
+    pub message: String,
+    /// Unique diagnostic code to look up more information
+    /// about this Diagnostic. Ideally also globally unique, and documented
+    /// in the toplevel crate's documentation for easy searching.
+    /// Rust path format (`foo::bar::baz`) is recommended, but more classic
+    /// codes like `E0123` will work just fine
+    #[cfg_attr(feature = "serde", serde(skip_serializing_if = "Option::is_none"))]
+    pub code: Option<String>,
+    /// [`Diagnostic`] severity. Intended to be used by
+    /// [`ReportHandler`](crate::ReportHandler)s to change the way different
+    /// [`Diagnostic`]s are displayed. Defaults to [`Severity::Error`]
+    #[cfg_attr(feature = "serde", serde(skip_serializing_if = "Option::is_none"))]
+    pub severity: Option<Severity>,
+    /// Additional help text related to this Diagnostic
+    #[cfg_attr(feature = "serde", serde(skip_serializing_if = "Option::is_none"))]
+    pub help: Option<String>,
+    /// URL to visit for a more detailed explanation/help about this
+    /// [`Diagnostic`].
+    #[cfg_attr(feature = "serde", serde(skip_serializing_if = "Option::is_none"))]
+    pub url: Option<String>,
+    /// Labels to apply to this `Diagnostic`'s [`Diagnostic::source_code`]
+    #[cfg_attr(feature = "serde", serde(skip_serializing_if = "Option::is_none"))]
+    pub labels: Option<Vec<LabeledSpan>>,
+}
+
+impl Display for MietteDiagnostic {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", &self.message)
+    }
+}
+
+impl Error for MietteDiagnostic {}
+
+impl Diagnostic for MietteDiagnostic {
+    fn code<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        self.code
+            .as_ref()
+            .map(Box::new)
+            .map(|c| c as Box<dyn Display>)
+    }
+
+    fn severity(&self) -> Option<Severity> {
+        self.severity
+    }
+
+    fn help<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        self.help
+            .as_ref()
+            .map(Box::new)
+            .map(|c| c as Box<dyn Display>)
+    }
+
+    fn url<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        self.url
+            .as_ref()
+            .map(Box::new)
+            .map(|c| c as Box<dyn Display>)
+    }
+
+    fn labels(&self) -> Option<Box<dyn Iterator<Item = LabeledSpan> + '_>> {
+        self.labels
+            .as_ref()
+            .map(|ls| ls.iter().cloned())
+            .map(Box::new)
+            .map(|b| b as Box<dyn Iterator<Item = LabeledSpan>>)
+    }
+}
+
+impl MietteDiagnostic {
+    /// Create a new dynamic diagnostic with the given message.
+    ///
+    /// # Examples
+    /// ```
+    /// use miette::{Diagnostic, MietteDiagnostic, Severity};
+    ///
+    /// let diag = MietteDiagnostic::new("Oops, something went wrong!");
+    /// assert_eq!(diag.to_string(), "Oops, something went wrong!");
+    /// assert_eq!(diag.message, "Oops, something went wrong!");
+    /// ```
+    pub fn new(message: impl Into<String>) -> Self {
+        Self {
+            message: message.into(),
+            labels: None,
+            severity: None,
+            code: None,
+            help: None,
+            url: None,
+        }
+    }
+
+    /// Return new diagnostic with the given code.
+    ///
+    /// # Examples
+    /// ```
+    /// use miette::{Diagnostic, MietteDiagnostic};
+    ///
+    /// let diag = MietteDiagnostic::new("Oops, something went wrong!").with_code("foo::bar::baz");
+    /// assert_eq!(diag.message, "Oops, something went wrong!");
+    /// assert_eq!(diag.code, Some("foo::bar::baz".to_string()));
+    /// ```
+    pub fn with_code(mut self, code: impl Into<String>) -> Self {
+        self.code = Some(code.into());
+        self
+    }
+
+    /// Return new diagnostic with the given severity.
+    ///
+    /// # Examples
+    /// ```
+    /// use miette::{Diagnostic, MietteDiagnostic, Severity};
+    ///
+    /// let diag = MietteDiagnostic::new("I warn you to stop!").with_severity(Severity::Warning);
+    /// assert_eq!(diag.message, "I warn you to stop!");
+    /// assert_eq!(diag.severity, Some(Severity::Warning));
+    /// ```
+    pub fn with_severity(mut self, severity: Severity) -> Self {
+        self.severity = Some(severity);
+        self
+    }
+
+    /// Return new diagnostic with the given help message.
+    ///
+    /// # Examples
+    /// ```
+    /// use miette::{Diagnostic, MietteDiagnostic};
+    ///
+    /// let diag = MietteDiagnostic::new("PC is not working").with_help("Try to reboot it again");
+    /// assert_eq!(diag.message, "PC is not working");
+    /// assert_eq!(diag.help, Some("Try to reboot it again".to_string()));
+    /// ```
+    pub fn with_help(mut self, help: impl Into<String>) -> Self {
+        self.help = Some(help.into());
+        self
+    }
+
+    /// Return new diagnostic with the given URL.
+    ///
+    /// # Examples
+    /// ```
+    /// use miette::{Diagnostic, MietteDiagnostic};
+    ///
+    /// let diag = MietteDiagnostic::new("PC is not working")
+    ///     .with_url("https://letmegooglethat.com/?q=Why+my+pc+doesn%27t+work");
+    /// assert_eq!(diag.message, "PC is not working");
+    /// assert_eq!(
+    ///     diag.url,
+    ///     Some("https://letmegooglethat.com/?q=Why+my+pc+doesn%27t+work".to_string())
+    /// );
+    /// ```
+    pub fn with_url(mut self, url: impl Into<String>) -> Self {
+        self.url = Some(url.into());
+        self
+    }
+
+    /// Return new diagnostic with the given label.
+    ///
+    /// Discards previous labels
+    ///
+    /// # Examples
+    /// ```
+    /// use miette::{Diagnostic, LabeledSpan, MietteDiagnostic};
+    ///
+    /// let source = "cpp is the best language";
+    ///
+    /// let label = LabeledSpan::at(0..3, "This should be Rust");
+    /// let diag = MietteDiagnostic::new("Wrong best language").with_label(label.clone());
+    /// assert_eq!(diag.message, "Wrong best language");
+    /// assert_eq!(diag.labels, Some(vec![label]));
+    /// ```
+    pub fn with_label(mut self, label: impl Into<LabeledSpan>) -> Self {
+        self.labels = Some(vec![label.into()]);
+        self
+    }
+
+    /// Return new diagnostic with the given labels.
+    ///
+    /// Discards previous labels
+    ///
+    /// # Examples
+    /// ```
+    /// use miette::{Diagnostic, LabeledSpan, MietteDiagnostic};
+    ///
+    /// let source = "helo wrld";
+    ///
+    /// let labels = vec![
+    ///     LabeledSpan::at_offset(3, "add 'l'"),
+    ///     LabeledSpan::at_offset(6, "add 'r'"),
+    /// ];
+    /// let diag = MietteDiagnostic::new("Typos in 'hello world'").with_labels(labels.clone());
+    /// assert_eq!(diag.message, "Typos in 'hello world'");
+    /// assert_eq!(diag.labels, Some(labels));
+    /// ```
+    pub fn with_labels(mut self, labels: impl IntoIterator<Item = LabeledSpan>) -> Self {
+        self.labels = Some(labels.into_iter().collect());
+        self
+    }
+
+    /// Return new diagnostic with new label added to the existing ones.
+    ///
+    /// # Examples
+    /// ```
+    /// use miette::{Diagnostic, LabeledSpan, MietteDiagnostic};
+    ///
+    /// let source = "helo wrld";
+    ///
+    /// let label1 = LabeledSpan::at_offset(3, "add 'l'");
+    /// let label2 = LabeledSpan::at_offset(6, "add 'r'");
+    /// let diag = MietteDiagnostic::new("Typos in 'hello world'")
+    ///     .and_label(label1.clone())
+    ///     .and_label(label2.clone());
+    /// assert_eq!(diag.message, "Typos in 'hello world'");
+    /// assert_eq!(diag.labels, Some(vec![label1, label2]));
+    /// ```
+    pub fn and_label(mut self, label: impl Into<LabeledSpan>) -> Self {
+        let mut labels = self.labels.unwrap_or_default();
+        labels.push(label.into());
+        self.labels = Some(labels);
+        self
+    }
+
+    /// Return new diagnostic with new labels added to the existing ones.
+    ///
+    /// # Examples
+    /// ```
+    /// use miette::{Diagnostic, LabeledSpan, MietteDiagnostic};
+    ///
+    /// let source = "helo wrld";
+    ///
+    /// let label1 = LabeledSpan::at_offset(3, "add 'l'");
+    /// let label2 = LabeledSpan::at_offset(6, "add 'r'");
+    /// let label3 = LabeledSpan::at_offset(9, "add '!'");
+    /// let diag = MietteDiagnostic::new("Typos in 'hello world!'")
+    ///     .and_label(label1.clone())
+    ///     .and_labels([label2.clone(), label3.clone()]);
+    /// assert_eq!(diag.message, "Typos in 'hello world!'");
+    /// assert_eq!(diag.labels, Some(vec![label1, label2, label3]));
+    /// ```
+    pub fn and_labels(mut self, labels: impl IntoIterator<Item = LabeledSpan>) -> Self {
+        let mut all_labels = self.labels.unwrap_or_default();
+        all_labels.extend(labels.into_iter());
+        self.labels = Some(all_labels);
+        self
+    }
+}
+
+#[cfg(feature = "serde")]
+#[test]
+fn test_serialize_miette_diagnostic() {
+    use serde_json::json;
+
+    use crate::diagnostic;
+
+    let diag = diagnostic!("message");
+    let json = json!({ "message": "message" });
+    assert_eq!(json!(diag), json);
+
+    let diag = diagnostic!(
+        code = "code",
+        help = "help",
+        url = "url",
+        labels = [
+            LabeledSpan::at_offset(0, "label1"),
+            LabeledSpan::at(1..3, "label2")
+        ],
+        severity = Severity::Warning,
+        "message"
+    );
+    let json = json!({
+        "message": "message",
+        "code": "code",
+        "help": "help",
+        "url": "url",
+        "severity": "Warning",
+        "labels": [
+            {
+                "span": {
+                    "offset": 0,
+                    "length": 0
+                },
+                "label": "label1"
+            },
+            {
+                "span": {
+                    "offset": 1,
+                    "length": 2
+                },
+                "label": "label2"
+            }
+        ]
+    });
+    assert_eq!(json!(diag), json);
+}
+
+#[cfg(feature = "serde")]
+#[test]
+fn test_deserialize_miette_diagnostic() {
+    use serde_json::json;
+
+    use crate::diagnostic;
+
+    let json = json!({ "message": "message" });
+    let diag = diagnostic!("message");
+    assert_eq!(diag, serde_json::from_value(json).unwrap());
+
+    let json = json!({
+        "message": "message",
+        "help": null,
+        "code": null,
+        "severity": null,
+        "url": null,
+        "labels": null
+    });
+    assert_eq!(diag, serde_json::from_value(json).unwrap());
+
+    let diag = diagnostic!(
+        code = "code",
+        help = "help",
+        url = "url",
+        labels = [
+            LabeledSpan::at_offset(0, "label1"),
+            LabeledSpan::at(1..3, "label2")
+        ],
+        severity = Severity::Warning,
+        "message"
+    );
+    let json = json!({
+        "message": "message",
+        "code": "code",
+        "help": "help",
+        "url": "url",
+        "severity": "Warning",
+        "labels": [
+            {
+                "span": {
+                    "offset": 0,
+                    "length": 0
+                },
+                "label": "label1"
+            },
+            {
+                "span": {
+                    "offset": 1,
+                    "length": 2
+                },
+                "label": "label2"
+            }
+        ]
+    });
+    assert_eq!(diag, serde_json::from_value(json).unwrap());
+}
diff --git a/src/named_source.rs b/src/named_source.rs
new file mode 100644
index 0000000..31ad1d1
--- /dev/null
+++ b/src/named_source.rs
@@ -0,0 +1,61 @@
+use crate::{MietteError, MietteSpanContents, SourceCode, SpanContents};
+
+/// Utility struct for when you have a regular [`SourceCode`] type that doesn't
+/// implement `name`. For example [`String`]. Or if you want to override the
+/// `name` returned by the `SourceCode`.
+pub struct NamedSource {
+    source: Box<dyn SourceCode + 'static>,
+    name: String,
+}
+
+impl std::fmt::Debug for NamedSource {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("NamedSource")
+            .field("name", &self.name)
+            .field("source", &"<redacted>");
+        Ok(())
+    }
+}
+
+impl NamedSource {
+    /// Create a new `NamedSource` using a regular [`SourceCode`] and giving
+    /// its returned [`SpanContents`] a name.
+    pub fn new(name: impl AsRef<str>, source: impl SourceCode + Send + Sync + 'static) -> Self {
+        Self {
+            source: Box::new(source),
+            name: name.as_ref().to_string(),
+        }
+    }
+
+    /// Gets the name of this `NamedSource`.
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    /// Returns a reference the inner [`SourceCode`] type for this
+    /// `NamedSource`.
+    pub fn inner(&self) -> &(dyn SourceCode + 'static) {
+        &*self.source
+    }
+}
+
+impl SourceCode for NamedSource {
+    fn read_span<'a>(
+        &'a self,
+        span: &crate::SourceSpan,
+        context_lines_before: usize,
+        context_lines_after: usize,
+    ) -> Result<Box<dyn SpanContents<'a> + 'a>, MietteError> {
+        let contents = self
+            .inner()
+            .read_span(span, context_lines_before, context_lines_after)?;
+        Ok(Box::new(MietteSpanContents::new_named(
+            self.name.clone(),
+            contents.data(),
+            *contents.span(),
+            contents.line(),
+            contents.column(),
+            contents.line_count(),
+        )))
+    }
+}
diff --git a/src/panic.rs b/src/panic.rs
new file mode 100644
index 0000000..ad98cac
--- /dev/null
+++ b/src/panic.rs
@@ -0,0 +1,86 @@
+use backtrace::Backtrace;
+use thiserror::Error;
+
+use crate::{self as miette, Context, Diagnostic, Result};
+
+/// Tells miette to render panics using its rendering engine.
+pub fn set_panic_hook() {
+    std::panic::set_hook(Box::new(move |info| {
+        let mut message = "Something went wrong".to_string();
+        let payload = info.payload();
+        if let Some(msg) = payload.downcast_ref::<&str>() {
+            message = msg.to_string();
+        }
+        if let Some(msg) = payload.downcast_ref::<String>() {
+            message = msg.clone();
+        }
+        let mut report: Result<()> = Err(Panic(message).into());
+        if let Some(loc) = info.location() {
+            report = report
+                .with_context(|| format!("at {}:{}:{}", loc.file(), loc.line(), loc.column()));
+        }
+        if let Err(err) = report.with_context(|| "Main thread panicked.".to_string()) {
+            eprintln!("Error: {:?}", err);
+        }
+    }));
+}
+
+#[derive(Debug, Error, Diagnostic)]
+#[error("{0}{}", Panic::backtrace())]
+#[diagnostic(help("set the `RUST_BACKTRACE=1` environment variable to display a backtrace."))]
+struct Panic(String);
+
+impl Panic {
+    fn backtrace() -> String {
+        use std::fmt::Write;
+        if let Ok(var) = std::env::var("RUST_BACKTRACE") {
+            if !var.is_empty() && var != "0" {
+                const HEX_WIDTH: usize = std::mem::size_of::<usize>() + 2;
+                // Padding for next lines after frame's address
+                const NEXT_SYMBOL_PADDING: usize = HEX_WIDTH + 6;
+                let mut backtrace = String::new();
+                let trace = Backtrace::new();
+                let frames = backtrace_ext::short_frames_strict(&trace).enumerate();
+                for (idx, (frame, sub_frames)) in frames {
+                    let ip = frame.ip();
+                    let _ = write!(backtrace, "\n{:4}: {:2$?}", idx, ip, HEX_WIDTH);
+
+                    let symbols = frame.symbols();
+                    if symbols.is_empty() {
+                        let _ = write!(backtrace, " - <unresolved>");
+                        continue;
+                    }
+
+                    for (idx, symbol) in symbols[sub_frames].iter().enumerate() {
+                        // Print symbols from this address,
+                        // if there are several addresses
+                        // we need to put it on next line
+                        if idx != 0 {
+                            let _ = write!(backtrace, "\n{:1$}", "", NEXT_SYMBOL_PADDING);
+                        }
+
+                        if let Some(name) = symbol.name() {
+                            let _ = write!(backtrace, " - {}", name);
+                        } else {
+                            let _ = write!(backtrace, " - <unknown>");
+                        }
+
+                        // See if there is debug information with file name and line
+                        if let (Some(file), Some(line)) = (symbol.filename(), symbol.lineno()) {
+                            let _ = write!(
+                                backtrace,
+                                "\n{:3$}at {}:{}",
+                                "",
+                                file.display(),
+                                line,
+                                NEXT_SYMBOL_PADDING
+                            );
+                        }
+                    }
+                }
+                return backtrace;
+            }
+        }
+        "".into()
+    }
+}
diff --git a/src/protocol.rs b/src/protocol.rs
new file mode 100644
index 0000000..7531db1
--- /dev/null
+++ b/src/protocol.rs
@@ -0,0 +1,685 @@
+/*!
+This module defines the core of the miette protocol: a series of types and
+traits that you can implement to get access to miette's (and related library's)
+full reporting and such features.
+*/
+use std::{
+    fmt::{self, Display},
+    fs,
+    panic::Location,
+};
+
+#[cfg(feature = "serde")]
+use serde::{Deserialize, Serialize};
+
+use crate::MietteError;
+
+/// Adds rich metadata to your Error that can be used by
+/// [`Report`](crate::Report) to print really nice and human-friendly error
+/// messages.
+pub trait Diagnostic: std::error::Error {
+    /// Unique diagnostic code that can be used to look up more information
+    /// about this `Diagnostic`. Ideally also globally unique, and documented
+    /// in the toplevel crate's documentation for easy searching. Rust path
+    /// format (`foo::bar::baz`) is recommended, but more classic codes like
+    /// `E0123` or enums will work just fine.
+    fn code<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        None
+    }
+
+    /// Diagnostic severity. This may be used by
+    /// [`ReportHandler`](crate::ReportHandler)s to change the display format
+    /// of this diagnostic.
+    ///
+    /// If `None`, reporters should treat this as [`Severity::Error`].
+    fn severity(&self) -> Option<Severity> {
+        None
+    }
+
+    /// Additional help text related to this `Diagnostic`. Do you have any
+    /// advice for the poor soul who's just run into this issue?
+    fn help<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        None
+    }
+
+    /// URL to visit for a more detailed explanation/help about this
+    /// `Diagnostic`.
+    fn url<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        None
+    }
+
+    /// Source code to apply this `Diagnostic`'s [`Diagnostic::labels`] to.
+    fn source_code(&self) -> Option<&dyn SourceCode> {
+        None
+    }
+
+    /// Labels to apply to this `Diagnostic`'s [`Diagnostic::source_code`]
+    fn labels(&self) -> Option<Box<dyn Iterator<Item = LabeledSpan> + '_>> {
+        None
+    }
+
+    /// Additional related `Diagnostic`s.
+    fn related<'a>(&'a self) -> Option<Box<dyn Iterator<Item = &'a dyn Diagnostic> + 'a>> {
+        None
+    }
+
+    /// The cause of the error.
+    fn diagnostic_source(&self) -> Option<&dyn Diagnostic> {
+        None
+    }
+}
+
+impl std::error::Error for Box<dyn Diagnostic> {
+    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+        (**self).source()
+    }
+
+    fn cause(&self) -> Option<&dyn std::error::Error> {
+        self.source()
+    }
+}
+
+impl<T: Diagnostic + Send + Sync + 'static> From<T>
+    for Box<dyn Diagnostic + Send + Sync + 'static>
+{
+    fn from(diag: T) -> Self {
+        Box::new(diag)
+    }
+}
+
+impl<T: Diagnostic + Send + Sync + 'static> From<T> for Box<dyn Diagnostic + Send + 'static> {
+    fn from(diag: T) -> Self {
+        Box::<dyn Diagnostic + Send + Sync>::from(diag)
+    }
+}
+
+impl<T: Diagnostic + Send + Sync + 'static> From<T> for Box<dyn Diagnostic + 'static> {
+    fn from(diag: T) -> Self {
+        Box::<dyn Diagnostic + Send + Sync>::from(diag)
+    }
+}
+
+impl From<&str> for Box<dyn Diagnostic> {
+    fn from(s: &str) -> Self {
+        From::from(String::from(s))
+    }
+}
+
+impl<'a> From<&str> for Box<dyn Diagnostic + Send + Sync + 'a> {
+    fn from(s: &str) -> Self {
+        From::from(String::from(s))
+    }
+}
+
+impl From<String> for Box<dyn Diagnostic> {
+    fn from(s: String) -> Self {
+        let err1: Box<dyn Diagnostic + Send + Sync> = From::from(s);
+        let err2: Box<dyn Diagnostic> = err1;
+        err2
+    }
+}
+
+impl From<String> for Box<dyn Diagnostic + Send + Sync> {
+    fn from(s: String) -> Self {
+        struct StringError(String);
+
+        impl std::error::Error for StringError {}
+        impl Diagnostic for StringError {}
+
+        impl Display for StringError {
+            fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+                Display::fmt(&self.0, f)
+            }
+        }
+
+        // Purposefully skip printing "StringError(..)"
+        impl fmt::Debug for StringError {
+            fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+                fmt::Debug::fmt(&self.0, f)
+            }
+        }
+
+        Box::new(StringError(s))
+    }
+}
+
+impl From<Box<dyn std::error::Error + Send + Sync>> for Box<dyn Diagnostic + Send + Sync> {
+    fn from(s: Box<dyn std::error::Error + Send + Sync>) -> Self {
+        #[derive(thiserror::Error)]
+        #[error(transparent)]
+        struct BoxedDiagnostic(Box<dyn std::error::Error + Send + Sync>);
+        impl fmt::Debug for BoxedDiagnostic {
+            fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+                fmt::Debug::fmt(&self.0, f)
+            }
+        }
+
+        impl Diagnostic for BoxedDiagnostic {}
+
+        Box::new(BoxedDiagnostic(s))
+    }
+}
+
+/**
+[`Diagnostic`] severity. Intended to be used by
+[`ReportHandler`](crate::ReportHandler)s to change the way different
+[`Diagnostic`]s are displayed. Defaults to [`Severity::Error`].
+*/
+#[derive(Copy, Clone, Debug, Eq, Ord, PartialEq, PartialOrd)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+pub enum Severity {
+    /// Just some help. Here's how you could be doing it better.
+    Advice,
+    /// Warning. Please take note.
+    Warning,
+    /// Critical failure. The program cannot continue.
+    /// This is the default severity, if you don't specify another one.
+    Error,
+}
+
+impl Default for Severity {
+    fn default() -> Self {
+        Severity::Error
+    }
+}
+
+#[cfg(feature = "serde")]
+#[test]
+fn test_serialize_severity() {
+    use serde_json::json;
+
+    assert_eq!(json!(Severity::Advice), json!("Advice"));
+    assert_eq!(json!(Severity::Warning), json!("Warning"));
+    assert_eq!(json!(Severity::Error), json!("Error"));
+}
+
+#[cfg(feature = "serde")]
+#[test]
+fn test_deserialize_severity() {
+    use serde_json::json;
+
+    let severity: Severity = serde_json::from_value(json!("Advice")).unwrap();
+    assert_eq!(severity, Severity::Advice);
+
+    let severity: Severity = serde_json::from_value(json!("Warning")).unwrap();
+    assert_eq!(severity, Severity::Warning);
+
+    let severity: Severity = serde_json::from_value(json!("Error")).unwrap();
+    assert_eq!(severity, Severity::Error);
+}
+
+/**
+Represents readable source code of some sort.
+
+This trait is able to support simple `SourceCode` types like [`String`]s, as
+well as more involved types like indexes into centralized `SourceMap`-like
+types, file handles, and even network streams.
+
+If you can read it, you can source it, and it's not necessary to read the
+whole thing--meaning you should be able to support `SourceCode`s which are
+gigabytes or larger in size.
+*/
+pub trait SourceCode: Send + Sync {
+    /// Read the bytes for a specific span from this SourceCode, keeping a
+    /// certain number of lines before and after the span as context.
+    fn read_span<'a>(
+        &'a self,
+        span: &SourceSpan,
+        context_lines_before: usize,
+        context_lines_after: usize,
+    ) -> Result<Box<dyn SpanContents<'a> + 'a>, MietteError>;
+}
+
+/// A labeled [`SourceSpan`].
+#[derive(Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+pub struct LabeledSpan {
+    #[cfg_attr(feature = "serde", serde(skip_serializing_if = "Option::is_none"))]
+    label: Option<String>,
+    span: SourceSpan,
+}
+
+impl LabeledSpan {
+    /// Makes a new labeled span.
+    pub const fn new(label: Option<String>, offset: ByteOffset, len: usize) -> Self {
+        Self {
+            label,
+            span: SourceSpan::new(SourceOffset(offset), SourceOffset(len)),
+        }
+    }
+
+    /// Makes a new labeled span using an existing span.
+    pub fn new_with_span(label: Option<String>, span: impl Into<SourceSpan>) -> Self {
+        Self {
+            label,
+            span: span.into(),
+        }
+    }
+
+    /// Makes a new label at specified span
+    ///
+    /// # Examples
+    /// ```
+    /// use miette::LabeledSpan;
+    ///
+    /// let source = "Cpp is the best";
+    /// let label = LabeledSpan::at(0..3, "should be Rust");
+    /// assert_eq!(
+    ///     label,
+    ///     LabeledSpan::new(Some("should be Rust".to_string()), 0, 3)
+    /// )
+    /// ```
+    pub fn at(span: impl Into<SourceSpan>, label: impl Into<String>) -> Self {
+        Self::new_with_span(Some(label.into()), span)
+    }
+
+    /// Makes a new label that points at a specific offset.
+    ///
+    /// # Examples
+    /// ```
+    /// use miette::LabeledSpan;
+    ///
+    /// let source = "(2 + 2";
+    /// let label = LabeledSpan::at_offset(4, "expected a closing parenthesis");
+    /// assert_eq!(
+    ///     label,
+    ///     LabeledSpan::new(Some("expected a closing parenthesis".to_string()), 4, 0)
+    /// )
+    /// ```
+    pub fn at_offset(offset: ByteOffset, label: impl Into<String>) -> Self {
+        Self::new(Some(label.into()), offset, 0)
+    }
+
+    /// Makes a new label without text, that underlines a specific span.
+    ///
+    /// # Examples
+    /// ```
+    /// use miette::LabeledSpan;
+    ///
+    /// let source = "You have an eror here";
+    /// let label = LabeledSpan::underline(12..16);
+    /// assert_eq!(label, LabeledSpan::new(None, 12, 4))
+    /// ```
+    pub fn underline(span: impl Into<SourceSpan>) -> Self {
+        Self::new_with_span(None, span)
+    }
+
+    /// Gets the (optional) label string for this `LabeledSpan`.
+    pub fn label(&self) -> Option<&str> {
+        self.label.as_deref()
+    }
+
+    /// Returns a reference to the inner [`SourceSpan`].
+    pub const fn inner(&self) -> &SourceSpan {
+        &self.span
+    }
+
+    /// Returns the 0-based starting byte offset.
+    pub const fn offset(&self) -> usize {
+        self.span.offset()
+    }
+
+    /// Returns the number of bytes this `LabeledSpan` spans.
+    pub const fn len(&self) -> usize {
+        self.span.len()
+    }
+
+    /// True if this `LabeledSpan` is empty.
+    pub const fn is_empty(&self) -> bool {
+        self.span.is_empty()
+    }
+}
+
+#[cfg(feature = "serde")]
+#[test]
+fn test_serialize_labeled_span() {
+    use serde_json::json;
+
+    assert_eq!(
+        json!(LabeledSpan::new(None, 0, 0)),
+        json!({
+            "span": { "offset": 0, "length": 0 }
+        })
+    );
+
+    assert_eq!(
+        json!(LabeledSpan::new(Some("label".to_string()), 0, 0)),
+        json!({
+            "label": "label",
+            "span": { "offset": 0, "length": 0 }
+        })
+    )
+}
+
+#[cfg(feature = "serde")]
+#[test]
+fn test_deserialize_labeled_span() {
+    use serde_json::json;
+
+    let span: LabeledSpan = serde_json::from_value(json!({
+        "label": null,
+        "span": { "offset": 0, "length": 0 }
+    }))
+    .unwrap();
+    assert_eq!(span, LabeledSpan::new(None, 0, 0));
+
+    let span: LabeledSpan = serde_json::from_value(json!({
+        "span": { "offset": 0, "length": 0 }
+    }))
+    .unwrap();
+    assert_eq!(span, LabeledSpan::new(None, 0, 0));
+
+    let span: LabeledSpan = serde_json::from_value(json!({
+        "label": "label",
+        "span": { "offset": 0, "length": 0 }
+    }))
+    .unwrap();
+    assert_eq!(span, LabeledSpan::new(Some("label".to_string()), 0, 0))
+}
+
+/**
+Contents of a [`SourceCode`] covered by [`SourceSpan`].
+
+Includes line and column information to optimize highlight calculations.
+*/
+pub trait SpanContents<'a> {
+    /// Reference to the data inside the associated span, in bytes.
+    fn data(&self) -> &'a [u8];
+    /// [`SourceSpan`] representing the span covered by this `SpanContents`.
+    fn span(&self) -> &SourceSpan;
+    /// An optional (file?) name for the container of this `SpanContents`.
+    fn name(&self) -> Option<&str> {
+        None
+    }
+    /// The 0-indexed line in the associated [`SourceCode`] where the data
+    /// begins.
+    fn line(&self) -> usize;
+    /// The 0-indexed column in the associated [`SourceCode`] where the data
+    /// begins, relative to `line`.
+    fn column(&self) -> usize;
+    /// Total number of lines covered by this `SpanContents`.
+    fn line_count(&self) -> usize;
+}
+
+/**
+Basic implementation of the [`SpanContents`] trait, for convenience.
+*/
+#[derive(Clone, Debug)]
+pub struct MietteSpanContents<'a> {
+    // Data from a [`SourceCode`], in bytes.
+    data: &'a [u8],
+    // span actually covered by this SpanContents.
+    span: SourceSpan,
+    // The 0-indexed line where the associated [`SourceSpan`] _starts_.
+    line: usize,
+    // The 0-indexed column where the associated [`SourceSpan`] _starts_.
+    column: usize,
+    // Number of line in this snippet.
+    line_count: usize,
+    // Optional filename
+    name: Option<String>,
+}
+
+impl<'a> MietteSpanContents<'a> {
+    /// Make a new [`MietteSpanContents`] object.
+    pub const fn new(
+        data: &'a [u8],
+        span: SourceSpan,
+        line: usize,
+        column: usize,
+        line_count: usize,
+    ) -> MietteSpanContents<'a> {
+        MietteSpanContents {
+            data,
+            span,
+            line,
+            column,
+            line_count,
+            name: None,
+        }
+    }
+
+    /// Make a new [`MietteSpanContents`] object, with a name for its 'file'.
+    pub const fn new_named(
+        name: String,
+        data: &'a [u8],
+        span: SourceSpan,
+        line: usize,
+        column: usize,
+        line_count: usize,
+    ) -> MietteSpanContents<'a> {
+        MietteSpanContents {
+            data,
+            span,
+            line,
+            column,
+            line_count,
+            name: Some(name),
+        }
+    }
+}
+
+impl<'a> SpanContents<'a> for MietteSpanContents<'a> {
+    fn data(&self) -> &'a [u8] {
+        self.data
+    }
+    fn span(&self) -> &SourceSpan {
+        &self.span
+    }
+    fn line(&self) -> usize {
+        self.line
+    }
+    fn column(&self) -> usize {
+        self.column
+    }
+    fn line_count(&self) -> usize {
+        self.line_count
+    }
+    fn name(&self) -> Option<&str> {
+        self.name.as_deref()
+    }
+}
+
+/// Span within a [`SourceCode`]
+#[derive(Clone, Copy, Debug, Eq, PartialEq, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+pub struct SourceSpan {
+    /// The start of the span.
+    offset: SourceOffset,
+    /// The total length of the span
+    length: usize,
+}
+
+impl SourceSpan {
+    /// Create a new [`SourceSpan`].
+    pub const fn new(start: SourceOffset, length: SourceOffset) -> Self {
+        Self {
+            offset: start,
+            length: length.offset(),
+        }
+    }
+
+    /// The absolute offset, in bytes, from the beginning of a [`SourceCode`].
+    pub const fn offset(&self) -> usize {
+        self.offset.offset()
+    }
+
+    /// Total length of the [`SourceSpan`], in bytes.
+    pub const fn len(&self) -> usize {
+        self.length
+    }
+
+    /// Whether this [`SourceSpan`] has a length of zero. It may still be useful
+    /// to point to a specific point.
+    pub const fn is_empty(&self) -> bool {
+        self.length == 0
+    }
+}
+
+impl From<(ByteOffset, usize)> for SourceSpan {
+    fn from((start, len): (ByteOffset, usize)) -> Self {
+        Self {
+            offset: start.into(),
+            length: len,
+        }
+    }
+}
+
+impl From<(SourceOffset, SourceOffset)> for SourceSpan {
+    fn from((start, len): (SourceOffset, SourceOffset)) -> Self {
+        Self::new(start, len)
+    }
+}
+
+impl From<std::ops::Range<ByteOffset>> for SourceSpan {
+    fn from(range: std::ops::Range<ByteOffset>) -> Self {
+        Self {
+            offset: range.start.into(),
+            length: range.len(),
+        }
+    }
+}
+
+impl From<SourceOffset> for SourceSpan {
+    fn from(offset: SourceOffset) -> Self {
+        Self { offset, length: 0 }
+    }
+}
+
+impl From<ByteOffset> for SourceSpan {
+    fn from(offset: ByteOffset) -> Self {
+        Self {
+            offset: offset.into(),
+            length: 0,
+        }
+    }
+}
+
+#[cfg(feature = "serde")]
+#[test]
+fn test_serialize_source_span() {
+    use serde_json::json;
+
+    assert_eq!(
+        json!(SourceSpan::from(0)),
+        json!({ "offset": 0, "length": 0})
+    )
+}
+
+#[cfg(feature = "serde")]
+#[test]
+fn test_deserialize_source_span() {
+    use serde_json::json;
+
+    let span: SourceSpan = serde_json::from_value(json!({ "offset": 0, "length": 0})).unwrap();
+    assert_eq!(span, SourceSpan::from(0))
+}
+
+/**
+"Raw" type for the byte offset from the beginning of a [`SourceCode`].
+*/
+pub type ByteOffset = usize;
+
+/**
+Newtype that represents the [`ByteOffset`] from the beginning of a [`SourceCode`]
+*/
+#[derive(Clone, Copy, Debug, Eq, PartialEq, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+pub struct SourceOffset(ByteOffset);
+
+impl SourceOffset {
+    /// Actual byte offset.
+    pub const fn offset(&self) -> ByteOffset {
+        self.0
+    }
+
+    /// Little utility to help convert 1-based line/column locations into
+    /// miette-compatible Spans
+    ///
+    /// This function is infallible: Giving an out-of-range line/column pair
+    /// will return the offset of the last byte in the source.
+    pub fn from_location(source: impl AsRef<str>, loc_line: usize, loc_col: usize) -> Self {
+        let mut line = 0usize;
+        let mut col = 0usize;
+        let mut offset = 0usize;
+        for char in source.as_ref().chars() {
+            if line + 1 >= loc_line && col + 1 >= loc_col {
+                break;
+            }
+            if char == '\n' {
+                col = 0;
+                line += 1;
+            } else {
+                col += 1;
+            }
+            offset += char.len_utf8();
+        }
+
+        SourceOffset(offset)
+    }
+
+    /// Returns an offset for the _file_ location of wherever this function is
+    /// called. If you want to get _that_ caller's location, mark this
+    /// function's caller with `#[track_caller]` (and so on and so forth).
+    ///
+    /// Returns both the filename that was given and the offset of the caller
+    /// as a [`SourceOffset`].
+    ///
+    /// Keep in mind that this fill only work if the file your Rust source
+    /// file was compiled from is actually available at that location. If
+    /// you're shipping binaries for your application, you'll want to ignore
+    /// the Err case or otherwise report it.
+    #[track_caller]
+    pub fn from_current_location() -> Result<(String, Self), MietteError> {
+        let loc = Location::caller();
+        Ok((
+            loc.file().into(),
+            fs::read_to_string(loc.file())
+                .map(|txt| Self::from_location(txt, loc.line() as usize, loc.column() as usize))?,
+        ))
+    }
+}
+
+impl From<ByteOffset> for SourceOffset {
+    fn from(bytes: ByteOffset) -> Self {
+        SourceOffset(bytes)
+    }
+}
+
+#[test]
+fn test_source_offset_from_location() {
+    let source = "f\n\noo\r\nbar";
+
+    assert_eq!(SourceOffset::from_location(source, 1, 1).offset(), 0);
+    assert_eq!(SourceOffset::from_location(source, 1, 2).offset(), 1);
+    assert_eq!(SourceOffset::from_location(source, 2, 1).offset(), 2);
+    assert_eq!(SourceOffset::from_location(source, 3, 1).offset(), 3);
+    assert_eq!(SourceOffset::from_location(source, 3, 2).offset(), 4);
+    assert_eq!(SourceOffset::from_location(source, 3, 3).offset(), 5);
+    assert_eq!(SourceOffset::from_location(source, 3, 4).offset(), 6);
+    assert_eq!(SourceOffset::from_location(source, 4, 1).offset(), 7);
+    assert_eq!(SourceOffset::from_location(source, 4, 2).offset(), 8);
+    assert_eq!(SourceOffset::from_location(source, 4, 3).offset(), 9);
+    assert_eq!(SourceOffset::from_location(source, 4, 4).offset(), 10);
+
+    // Out-of-range
+    assert_eq!(
+        SourceOffset::from_location(source, 5, 1).offset(),
+        source.len()
+    );
+}
+
+#[cfg(feature = "serde")]
+#[test]
+fn test_serialize_source_offset() {
+    use serde_json::json;
+
+    assert_eq!(json!(SourceOffset::from(0)), 0)
+}
+
+#[cfg(feature = "serde")]
+#[test]
+fn test_deserialize_source_offset() {
+    let offset: SourceOffset = serde_json::from_str("0").unwrap();
+    assert_eq!(offset, SourceOffset::from(0))
+}
diff --git a/src/source_impls.rs b/src/source_impls.rs
new file mode 100644
index 0000000..e43a665
--- /dev/null
+++ b/src/source_impls.rs
@@ -0,0 +1,301 @@
+/*!
+Default trait implementations for [`SourceCode`].
+*/
+use std::{
+    borrow::{Cow, ToOwned},
+    collections::VecDeque,
+    fmt::Debug,
+    sync::Arc,
+};
+
+use crate::{MietteError, MietteSpanContents, SourceCode, SourceSpan, SpanContents};
+
+fn context_info<'a>(
+    input: &'a [u8],
+    span: &SourceSpan,
+    context_lines_before: usize,
+    context_lines_after: usize,
+) -> Result<MietteSpanContents<'a>, MietteError> {
+    let mut offset = 0usize;
+    let mut line_count = 0usize;
+    let mut start_line = 0usize;
+    let mut start_column = 0usize;
+    let mut before_lines_starts = VecDeque::new();
+    let mut current_line_start = 0usize;
+    let mut end_lines = 0usize;
+    let mut post_span = false;
+    let mut post_span_got_newline = false;
+    let mut iter = input.iter().copied().peekable();
+    while let Some(char) = iter.next() {
+        if matches!(char, b'\r' | b'\n') {
+            line_count += 1;
+            if char == b'\r' && iter.next_if_eq(&b'\n').is_some() {
+                offset += 1;
+            }
+            if offset < span.offset() {
+                // We're before the start of the span.
+                start_column = 0;
+                before_lines_starts.push_back(current_line_start);
+                if before_lines_starts.len() > context_lines_before {
+                    start_line += 1;
+                    before_lines_starts.pop_front();
+                }
+            } else if offset >= span.offset() + span.len().saturating_sub(1) {
+                // We're after the end of the span, but haven't necessarily
+                // started collecting end lines yet (we might still be
+                // collecting context lines).
+                if post_span {
+                    start_column = 0;
+                    if post_span_got_newline {
+                        end_lines += 1;
+                    } else {
+                        post_span_got_newline = true;
+                    }
+                    if end_lines >= context_lines_after {
+                        offset += 1;
+                        break;
+                    }
+                }
+            }
+            current_line_start = offset + 1;
+        } else if offset < span.offset() {
+            start_column += 1;
+        }
+
+        if offset >= (span.offset() + span.len()).saturating_sub(1) {
+            post_span = true;
+            if end_lines >= context_lines_after {
+                offset += 1;
+                break;
+            }
+        }
+
+        offset += 1;
+    }
+
+    if offset >= (span.offset() + span.len()).saturating_sub(1) {
+        let starting_offset = before_lines_starts.front().copied().unwrap_or_else(|| {
+            if context_lines_before == 0 {
+                span.offset()
+            } else {
+                0
+            }
+        });
+        Ok(MietteSpanContents::new(
+            &input[starting_offset..offset],
+            (starting_offset, offset - starting_offset).into(),
+            start_line,
+            if context_lines_before == 0 {
+                start_column
+            } else {
+                0
+            },
+            line_count,
+        ))
+    } else {
+        Err(MietteError::OutOfBounds)
+    }
+}
+
+impl SourceCode for [u8] {
+    fn read_span<'a>(
+        &'a self,
+        span: &SourceSpan,
+        context_lines_before: usize,
+        context_lines_after: usize,
+    ) -> Result<Box<dyn SpanContents<'a> + 'a>, MietteError> {
+        let contents = context_info(self, span, context_lines_before, context_lines_after)?;
+        Ok(Box::new(contents))
+    }
+}
+
+impl<'src> SourceCode for &'src [u8] {
+    fn read_span<'a>(
+        &'a self,
+        span: &SourceSpan,
+        context_lines_before: usize,
+        context_lines_after: usize,
+    ) -> Result<Box<dyn SpanContents<'a> + 'a>, MietteError> {
+        <[u8] as SourceCode>::read_span(self, span, context_lines_before, context_lines_after)
+    }
+}
+
+impl SourceCode for Vec<u8> {
+    fn read_span<'a>(
+        &'a self,
+        span: &SourceSpan,
+        context_lines_before: usize,
+        context_lines_after: usize,
+    ) -> Result<Box<dyn SpanContents<'a> + 'a>, MietteError> {
+        <[u8] as SourceCode>::read_span(self, span, context_lines_before, context_lines_after)
+    }
+}
+
+impl SourceCode for str {
+    fn read_span<'a>(
+        &'a self,
+        span: &SourceSpan,
+        context_lines_before: usize,
+        context_lines_after: usize,
+    ) -> Result<Box<dyn SpanContents<'a> + 'a>, MietteError> {
+        <[u8] as SourceCode>::read_span(
+            self.as_bytes(),
+            span,
+            context_lines_before,
+            context_lines_after,
+        )
+    }
+}
+
+/// Makes `src: &'static str` or `struct S<'a> { src: &'a str }` usable.
+impl<'s> SourceCode for &'s str {
+    fn read_span<'a>(
+        &'a self,
+        span: &SourceSpan,
+        context_lines_before: usize,
+        context_lines_after: usize,
+    ) -> Result<Box<dyn SpanContents<'a> + 'a>, MietteError> {
+        <str as SourceCode>::read_span(self, span, context_lines_before, context_lines_after)
+    }
+}
+
+impl SourceCode for String {
+    fn read_span<'a>(
+        &'a self,
+        span: &SourceSpan,
+        context_lines_before: usize,
+        context_lines_after: usize,
+    ) -> Result<Box<dyn SpanContents<'a> + 'a>, MietteError> {
+        <str as SourceCode>::read_span(self, span, context_lines_before, context_lines_after)
+    }
+}
+
+impl<T: ?Sized + SourceCode> SourceCode for Arc<T> {
+    fn read_span<'a>(
+        &'a self,
+        span: &SourceSpan,
+        context_lines_before: usize,
+        context_lines_after: usize,
+    ) -> Result<Box<dyn SpanContents<'a> + 'a>, MietteError> {
+        self.as_ref()
+            .read_span(span, context_lines_before, context_lines_after)
+    }
+}
+
+impl<T: ?Sized + SourceCode + ToOwned> SourceCode for Cow<'_, T>
+where
+    // The minimal bounds are used here.
+    // `T::Owned` need not be
+    // `SourceCode`, because `&T`
+    // can always be obtained from
+    // `Cow<'_, T>`.
+    T::Owned: Debug + Send + Sync,
+{
+    fn read_span<'a>(
+        &'a self,
+        span: &SourceSpan,
+        context_lines_before: usize,
+        context_lines_after: usize,
+    ) -> Result<Box<dyn SpanContents<'a> + 'a>, MietteError> {
+        self.as_ref()
+            .read_span(span, context_lines_before, context_lines_after)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn basic() -> Result<(), MietteError> {
+        let src = String::from("foo\n");
+        let contents = src.read_span(&(0, 4).into(), 0, 0)?;
+        assert_eq!("foo\n", std::str::from_utf8(contents.data()).unwrap());
+        assert_eq!(0, contents.line());
+        assert_eq!(0, contents.column());
+        Ok(())
+    }
+
+    #[test]
+    fn shifted() -> Result<(), MietteError> {
+        let src = String::from("foobar");
+        let contents = src.read_span(&(3, 3).into(), 1, 1)?;
+        assert_eq!("foobar", std::str::from_utf8(contents.data()).unwrap());
+        assert_eq!(0, contents.line());
+        assert_eq!(0, contents.column());
+        Ok(())
+    }
+
+    #[test]
+    fn middle() -> Result<(), MietteError> {
+        let src = String::from("foo\nbar\nbaz\n");
+        let contents = src.read_span(&(4, 4).into(), 0, 0)?;
+        assert_eq!("bar\n", std::str::from_utf8(contents.data()).unwrap());
+        assert_eq!(1, contents.line());
+        assert_eq!(0, contents.column());
+        Ok(())
+    }
+
+    #[test]
+    fn middle_of_line() -> Result<(), MietteError> {
+        let src = String::from("foo\nbarbar\nbaz\n");
+        let contents = src.read_span(&(7, 4).into(), 0, 0)?;
+        assert_eq!("bar\n", std::str::from_utf8(contents.data()).unwrap());
+        assert_eq!(1, contents.line());
+        assert_eq!(3, contents.column());
+        Ok(())
+    }
+
+    #[test]
+    fn with_crlf() -> Result<(), MietteError> {
+        let src = String::from("foo\r\nbar\r\nbaz\r\n");
+        let contents = src.read_span(&(5, 5).into(), 0, 0)?;
+        assert_eq!("bar\r\n", std::str::from_utf8(contents.data()).unwrap());
+        assert_eq!(1, contents.line());
+        assert_eq!(0, contents.column());
+        Ok(())
+    }
+
+    #[test]
+    fn with_context() -> Result<(), MietteError> {
+        let src = String::from("xxx\nfoo\nbar\nbaz\n\nyyy\n");
+        let contents = src.read_span(&(8, 3).into(), 1, 1)?;
+        assert_eq!(
+            "foo\nbar\nbaz\n",
+            std::str::from_utf8(contents.data()).unwrap()
+        );
+        assert_eq!(1, contents.line());
+        assert_eq!(0, contents.column());
+        Ok(())
+    }
+
+    #[test]
+    fn multiline_with_context() -> Result<(), MietteError> {
+        let src = String::from("aaa\nxxx\n\nfoo\nbar\nbaz\n\nyyy\nbbb\n");
+        let contents = src.read_span(&(9, 11).into(), 1, 1)?;
+        assert_eq!(
+            "\nfoo\nbar\nbaz\n\n",
+            std::str::from_utf8(contents.data()).unwrap()
+        );
+        assert_eq!(2, contents.line());
+        assert_eq!(0, contents.column());
+        let span: SourceSpan = (8, 14).into();
+        assert_eq!(&span, contents.span());
+        Ok(())
+    }
+
+    #[test]
+    fn multiline_with_context_line_start() -> Result<(), MietteError> {
+        let src = String::from("one\ntwo\n\nthree\nfour\nfive\n\nsix\nseven\n");
+        let contents = src.read_span(&(2, 0).into(), 2, 2)?;
+        assert_eq!(
+            "one\ntwo\n\n",
+            std::str::from_utf8(contents.data()).unwrap()
+        );
+        assert_eq!(0, contents.line());
+        assert_eq!(0, contents.column());
+        let span: SourceSpan = (0, 9).into();
+        assert_eq!(&span, contents.span());
+        Ok(())
+    }
+}
author	Matthew Maurer <mmaurer@google.com>	2023-06-27 00:15:42 +0000
committer	Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>	2023-06-27 00:15:42 +0000
commit	b89e57f0a8c2e009aa6145b1a9bbe5f5baef3a34 (patch)
tree	4e2459aa3960ec4d7332844de024ea249f394b4f
parent	b11879fb7d28d05b2bf4422962504020dc7745e9 (diff)
parent	f65d43dce7f4462d83a52b909fb2d07f1f10ad6e (diff)
download	miette-b89e57f0a8c2e009aa6145b1a9bbe5f5baef3a34.tar.gz