pre-commit workflow (pallets/flask)

The pre-commit workflow from pallets/flask, explained and optimized by Latchkey.

CI health: C - fair

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Source: pallets/flask.github/workflows/pre-commit.yamlLicense BSD-3-ClauseView source

What it does

This is the pre-commit workflow from the pallets/flask repository, a real project running GitHub Actions. It is shown here with attribution under its BSD-3-Clause license.

Below, Latchkey shows a faster, safer version produced by its optimization engine.

The workflow

workflow (.yml)

name: pre-commit
on:
  pull_request:
  push:
    branches: [main, stable]
permissions: {}
concurrency:
  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
  cancel-in-progress: true
jobs:
  main:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
        with:
          persist-credentials: false
      - uses: astral-sh/setup-uv@cec208311dfd045dd5311c1add060b2062131d57 # v8.0.0
        with:
          enable-cache: true
          prune-cache: false
      - uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405 # v6.2.0
        id: setup-python
        with:
          python-version-file: pyproject.toml
      - uses: actions/cache@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v5.0.4
        with:
          path: ~/.cache/pre-commit
          key: pre-commit|${{ hashFiles('pyproject.toml', '.pre-commit-config.yaml') }}
      - run: uv run --locked --no-default-groups --group pre-commit pre-commit run --show-diff-on-failure --color=always --all-files

The same workflow, on Latchkey

Estimated ~20% faster on cache hits, plus fewer wasted runs and a safer supply chain. Added and changed lines are highlighted.

name: pre-commit
on:
  pull_request:
  push:
    branches: [main, stable]
permissions: {}
concurrency:
  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
  cancel-in-progress: true
jobs:
  main:
    timeout-minutes: 30
    runs-on: latchkey-small
    steps:
      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
        with:
          persist-credentials: false
      - uses: astral-sh/setup-uv@cec208311dfd045dd5311c1add060b2062131d57 # v8.0.0
        with:
          enable-cache: true
          prune-cache: false
      - uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405 # v6.2.0
        id: setup-python
        with:
          cache: 'pip'
          python-version-file: pyproject.toml
      - uses: actions/cache@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v5.0.4
        with:
          path: ~/.cache/pre-commit
          key: pre-commit|${{ hashFiles('pyproject.toml', '.pre-commit-config.yaml') }}
      - run: uv run --locked --no-default-groups --group pre-commit pre-commit run --show-diff-on-failure --color=always --all-files

What changed

Run on Latchkey managed runners with one line (runs-on), which apply the fixes below automatically and self-heal transient failures. This example uses latchkey-small; pick the runner size that fits the job.
Cache dependency installs on the setup step so they are served from cache.
Add a job timeout so a hung step cannot burn hours of runner time.

This workflow runs 1 job per trigger. On Latchkey the same minutes cost up to 58% less than GitHub-hosted, with zero queue time.

Actions used in this workflow

actions/checkout astral-sh/setup-uv actions/setup-python actions/cache