Linting

bun lint lints JavaScript and TypeScript with oxlint and adds the Node.js-to-Bun rules of n2b, which report Node.js APIs that have a faster Bun equivalent.

bun lint

src/index.ts:3:7 warning eslint(no-unused-vars) Variable 'x' is declared but never used.
src/fs.ts:1:1 warning n2b(node-fs-readfile) Use Bun.file(path).text() instead of fs.readFile
  help: const text = await Bun.file(path).text();
n2b: 0 error(s), 1 warning(s)

bun lint exits with code 1 if it finds an error, and 0 otherwise. Pass --deny-warnings to fail on warnings too.

With no paths, oxlint lints the working directory. Pass files or directories to lint only those.

bun lint src test

How oxlint is installed

oxlint is not part of the bun binary. The first bun lint downloads a pinned version with bun x and caches it, so later runs start immediately and work offline. bun lint uses node_modules/.bin/oxlint instead when the project installs oxlint itself.

To use another version, set version in bunfig.toml or install oxlint in the project.

Fix problems

--fix applies the safe fixes of oxlint and n2b.

bun lint --fix

Lint only changed files

--since lints the files changed since a git ref, plus staged, unstaged and untracked files.

bun lint --since=main

Workspaces

--workspaces lints every package listed in the workspaces field of package.json. --filter lints the packages whose name or path matches.

bun lint --workspaces
bun lint --filter 'packages/*'

Output formats

--format selects the reporter: default, json, sarif, github, stylish, unix, checkstyle, junit or gitlab. In json and sarif output, the n2b findings are merged into the oxlint report, so one file holds every diagnostic.

bun lint --format=sarif > lint.sarif

Configure

bun lint reads .oxlintrc.json the same way oxlint does. See the oxlint configuration reference for rules, plugins and overrides.

{
  "plugins": ["typescript", "unicorn", "import"],
  "rules": {
    "no-console": "warn"
  },
  "ignorePatterns": ["dist/**"]
}

Project defaults go in the [lint] section of bunfig.toml.

[lint]
# oxlint configuration file
config = ".oxlintrc.json"
# paths linted when none are given
paths = ["src", "test"]
# glob patterns to skip
ignore = ["dist/**"]
# run the n2b rules (default: true)
n2b = true
# more oxlint arguments
args = ["--deny-warnings"]
# oxlint version to download
version = "1.87.0"

Flags

Every other flag goes to oxlint, for example -D correctness -A no-console or --type-aware.

package.json scripts

If package.json has a lint script, bun lint runs that script, as it did before bun lint existed. Inside the script, bun lint is the command:

{
  "scripts": {
    "lint": "bun lint --deny-warnings"
  }
}

To format code, use bun fmt.