prefer-knip-in-ci

Suggests running knip, the JavaScript/TypeScript unused-code and unused-dependency checker, in CI.

What it detects

• a package.json that declares a non-trivial dependency set (5 or more direct dependencies), for a single package or a workspace
• no knip usage anywhere in the repository:
  • no knip dependency
  • no knip script or knip field in package.json
  • no knip command in any workflow
  • no knip config file (knip.json, knip.jsonc, .knip.json, .knip.jsonc, knip.config.ts/js/mjs/cjs, knip.ts, knip.js)

Small projects are skipped: below five direct dependencies the unused-dependency savings rarely justify adding a checker. This is the JS/TS counterpart to prefer-cargo-shear-in-ci.

Why it matters

knip finds unused files, exports, and dependencies across a JavaScript/TypeScript project. Unused dependencies are still installed, so they slow installs and can add type-checking and resolution work, and unused files/exports add build and test work. Removing the findings shrinks node_modules and CI time.

Suggested action

Add knip to the project (a knip devDependency plus a config if needed) and run it in CI, for example with a knip script or an npx knip step. Start from the default config, review the findings, and add ignore entries for intentional dynamic imports and entry points.

Measurement

Compare dependency count, install time, type-check time, and CI wall-clock time before and after removing knip findings.

References

• https://knip.dev/