Setup CI and other integrations

You can - and should - set up your CI pipeline to run Oxfmt and fail the build on formatting differences.

This page also covers other integrations you may want to include, like git pre-commit hooks.

CI

GitHub Actions

First, add a fmt:check script to your package.json if you don't have one already:

package.json

{
  "scripts": {
    "fmt:check": "oxfmt --check"
  }
}

And then add a job to your GitHub Actions workflow:

.github/workflows/ci.yml

name: CI

on:
  pull_request:
  push:
    branches: [main]

permissions: {}

jobs:
  format:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6

      - uses: pnpm/action-setup@v4

      - uses: actions/setup-node@v6
        with:
          node-version: lts/*
          cache: pnpm

      # Or yarn, npm, etc.
      - run: pnpm install --frozen-lockfile
      - run: pnpm run fmt:check

Autofix formatting issues

If you find that you often forget to run Oxfmt before opening PRs, and don't or can't use pre-commit hooks, you can add an autofix step to your CI workflow using autofix.ci.

See https://autofix.ci/setup for more details, you will need to install the relevant GitHub App as well.

Below is an example GitHub Actions workflow you can use:

.github/workflows/autofix.yml

name: autofix.ci # needs to use this name

on:
  pull_request:
  push:
    branches: ["main"]

permissions:
  contents: read

jobs:
  autofix:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6

      - uses: pnpm/action-setup@v4

      - uses: actions/setup-node@v6
        with:
          node-version: lts/*
          cache: pnpm

      # Or yarn, npm, etc.
      - run: pnpm install --frozen-lockfile

      # Run oxfmt to write changes, autofix.ci will commit them if there are any differences.
      # Be sure to add a `fmt` script to your `package.json` if you haven't already.
      - run: pnpm run fmt

      # NOTE: It is strongly recommended to use the latest SHA hash for this action instead of the version number. (See https://autofix.ci/setup for more details.)
      - uses: autofix-ci/action@1.3.2

GitLab CI

If you use GitLab CI, you can set up Oxfmt to enforce code formatting as part of your CI pipeline.

First, add a fmt:check script to your package.json if you don't have one already:

package.json

{
  "scripts": {
    "fmt:check": "oxfmt --check"
  }
}

And then add a job to your .gitlab-ci.yml, to check that all code is formatted correctly:

.gitlab-ci.yml

oxfmt:
  image: node:lts
  stage: test
  before_script:
    # Or pnpm, yarn, etc.
    - npm install
  script:
    - npm run fmt:check

You may also want to add caching for your package manager to speed up installs.

Pre-commit hook

To auto-format staged files, use oxfmt --no-error-on-unmatched-pattern. This formats all supported files and avoids errors when no files match (e.g., only Ruby files are staged).

Use --check to verify formatting without writing files.

For lint-staged, add to package.json:

package.json

{
  "lint-staged": {
    "*": "oxfmt --no-error-on-unmatched-pattern"
  }
}

To automatically install the git hook when installing dependencies, considering also using husky.