prefer-fail-fast

Rule catalog ID: R015

Targeted pattern scope

GitHub Actions workflow YAML files that use matrix strategies.

What this rule reports

This rule reports jobs that explicitly set strategy.fail-fast to false.

Why this rule exists

Leaving fail-fast enabled can save runner time and reduce queue pressure when one matrix job already proves the matrix is failing.

❌ Incorrect

jobs:
  test:
    name: Test
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        node: [20, 22]

✅ Correct

jobs:
  test:
    name: Test
    runs-on: ubuntu-latest
    strategy:
      fail-fast: true
      matrix:
        node: [20, 22]

Additional examples

For larger repositories, this rule is often enabled together with one of the published presets so violations are caught in pull requests before workflow changes are merged.

ESLint flat config example

import githubActions from "eslint-plugin-github-actions-2";

export default [
  {
    files: ["**/*.{yml,yaml}"],
    plugins: {
      "github-actions": githubActions,
    },
    rules: {
      "github-actions/prefer-fail-fast": "error",
    },
  },
];

When not to use it

You can disable this rule when its policy does not match your repository standards, or when equivalent enforcement is already handled by another policy tool.

Targeted pattern scope​

What this rule reports​

Why this rule exists​

❌ Incorrect​

✅ Correct​

Additional examples​

ESLint flat config example​

When not to use it​

Further reading​