Language support

TypeScript (primary)

TypeScript is cofferdam's primary surface: every flagship check — orphan exports, layering, complexity, suppression hygiene — targets TS / TSX / JS / JSX / MJS / CJS via the oxc parser.

HTML (build-output / plugin surface)

An HTML adapter ships under crates/cofferdam-html, built on tree-sitter-html. It backs two entry points: built-in and plugin checks can target .html files directly under cofferdam check (files: { extensions: ["html"] } for plugins), and .html/.htm files under a built output directory via cofferdam verify --dist. The plugin AstView/LineView surface is the same shape used for TypeScript — findAll("Element"), .attributes, .children — documented in the Author guide and demonstrated end-to-end in SEO-grade checking.

Markdown / MDX (plugin surface, opt-in)

.md/.mdx files aren't discovered by default — walking every README and changelog in a repo on every run would inflate the file walk for projects that never asked for it. A project that wants plugin checks over text content (blog posts, docs) opts in per-project:

# cofferdam.toml
[engine]
extra_extensions = ["md", "mdx"]

Markdown files get no whole-file parse (file.ast is null on the plugin surface, matching Astro's non-goal), but file.text and line-scan LineViews are populated, so Pattern-A regex/line-based plugin checks (frontmatter length, heading structure, link density) work the same way they do for .astro. No built-in check targets Markdown — this is a plugin-only surface.

Rust (second language, dogfood)

A Rust adapter ships under crates/cofferdam-rust, exercising the engine's per-language dispatch (cd-91zc). Three checks today:

• Rust.NoUnwrapInLib — no .unwrap() in library code
• Rust.NoUnimplementedInNonTest — no unimplemented!() outside tests
• Rust.MissingPubDoc — public items need doc comments

A CI dogfood job runs cofferdam against its own Rust workspace on every PR.

The Rust adapter is load-bearing for the polylingual architecture pledge: until a second domain existed, "framework, not TS-tool" was theory. It now ships as a working second parser feeding the same Check trait the TS adapter uses.

Typst (package linting, separate subcommand)

cofferdam typst <dir> lints a Typst package directory bound for Typst Universe. It is a subcommand rather than an adapter because its unit of analysis is a directory — typst.toml, LICENSE, README.md and the published bundle together — which does not fit the engine's per-file, AST-oriented Check trait. The crate (crates/cofferdam-typst) defines its own TypstCheck trait and reuses cofferdam_core::Issue, so findings render through the same formatters as everything else.

cofferdam typst .                # lint the package in the current directory
cofferdam typst pkg/ --robot     # JSON, for CI

Eleven checks ship today, all keyed to Universe's submission rules:

Check	Catches
Typst.ManifestRequiredFields	A [package] table missing name, version, entrypoint, authors or the other required fields
Typst.PackageNameNotCanonical	A name that collides with a generic or reserved one already common in the registry
Typst.PackageNameKebabCase	Uppercase or underscores in the package name
Typst.DescriptionStyle	A description missing its full stop, or opening with A /An
Typst.ManifestVersionMatchesDir	A manifest version that disagrees with the preview/<name>/<version>/ path it sits under
Typst.ReadmeVersionMatchesManifest	@preview/<name>:X.Y.Z examples in the README pinned to a stale version
Typst.RelativeImportInPublishedReadme	README examples importing by relative path, which works locally and breaks for everyone else
Typst.LicenseFileMatchesSPDX	A missing LICENSE, or a manifest license field that is not a valid SPDX identifier
Typst.LicenseMissing	No LICENSE file at all — Universe requires one
Typst.BundleIncludesPdf	Root-level PDFs bloating the published bundle
Typst.ChangelogMissing	No CHANGELOG.md; not a hard Universe rule, but expected of a package people depend on

These checks are not in the check catalogue, which is generated from the engine's built-in set and does not yet reach the Typst trait (CD-303). Until it does, cofferdam typst --robot is the authoritative list.

Future adapters

SQL, IaC, and GraphQL adapters follow the same shape — a parser feeding the shared Check trait and category model. See the phased roadmap.