CI workflow (twardoch/fonttools-opentype-feature-freezer)

The CI workflow from twardoch/fonttools-opentype-feature-freezer, explained and optimized by Latchkey.

What it does

This is the CI workflow from the twardoch/fonttools-opentype-feature-freezer repository, a real project running GitHub Actions. It is shown here with attribution under its Apache-2.0 license.

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

The workflow

name: CI

on:
  push:
    branches: [master, main]
  pull_request:
  workflow_dispatch:

concurrency:
  group: ci-${{ github.ref }}
  cancel-in-progress: true

jobs:
  test:
    name: Test (Python ${{ matrix.python-version }})
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13"]
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0

      - name: Install uv
        uses: astral-sh/setup-uv@v5
        with:
          python-version: ${{ matrix.python-version }}

      - name: Lint (ruff)
        run: uvx ruff check src tests

      - name: Format check (ruff)
        run: uvx ruff format --check src tests

      - name: Type check (mypy)
        run: uv run --with mypy --with fonttools --with pytest mypy src tests

      - name: Run tests
        run: uv run --with pytest --with pytest-cov --with fonttools pytest tests

The same workflow, on Latchkey

Removes redundant runs and caps runaway jobs. Added and changed lines are highlighted.

name: CI
 
on:
  push:
    branches: [master, main]
  pull_request:
  workflow_dispatch:
 
concurrency:
  group: ci-${{ github.ref }}
  cancel-in-progress: true
 
jobs:
  test:
    timeout-minutes: 30
    name: Test (Python ${{ matrix.python-version }})
    runs-on: latchkey-small
    strategy:
      fail-fast: false
      matrix:
        python-version: ["3.9", "3.10", "3.11", "3.12", "3.13"]
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
 
      - name: Install uv
        uses: astral-sh/setup-uv@v5
        with:
          python-version: ${{ matrix.python-version }}
 
      - name: Lint (ruff)
        run: uvx ruff check src tests
 
      - name: Format check (ruff)
        run: uvx ruff format --check src tests
 
      - name: Type check (mypy)
        run: uv run --with mypy --with fonttools --with pytest mypy src tests
 
      - name: Run tests
        run: uv run --with pytest --with pytest-cov --with fonttools pytest tests
 

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.
• Add a job timeout so a hung step cannot burn hours of runner time.

1 third-party action is referenced by a movable tag. Pin it to the commit SHA (Latchkey resolves and applies this automatically) so a repointed tag cannot change what runs.

This workflow runs 1 job (5 with the matrix expanded) per trigger. On Latchkey the same minutes cost up to 58% less than GitHub-hosted, with zero queue time.

Actions used in this workflow