Format and Lint workflow (hbldh/bleak)

The Format and Lint workflow from hbldh/bleak, explained and optimized by Latchkey.

What it does

This is the Format and Lint workflow from the hbldh/bleak repository, a real project running GitHub Actions. It is shown here with attribution under its MIT license.

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

The workflow

name: Format and Lint

on:
  push:
    branches: [master, develop]
  pull_request:

jobs:
  format_and_lint:
    name: "Format and lint"
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Install the latest version of uv
        uses: astral-sh/setup-uv@v6
        with:
          version: "latest"

      - name: Check import sort with isort, code formatting with black, and lint with flake8
        run: uv run poe lint --checkonly

      - name: Build docs
        run: uv run poe docs

The same workflow, on Latchkey

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

name: Format and Lint
 
on:
  push:
    branches: [master, develop]
  pull_request:
 
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true
 
jobs:
  format_and_lint:
    timeout-minutes: 30
    name: "Format and lint"
    runs-on: latchkey-small
    steps:
      - uses: actions/checkout@v4
 
      - name: Install the latest version of uv
        uses: astral-sh/setup-uv@v6
        with:
          version: "latest"
 
      - name: Check import sort with isort, code formatting with black, and lint with flake8
        run: uv run poe lint --checkonly
 
      - name: Build docs
        run: uv run poe docs
 

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.
• Cancel superseded runs when a branch or PR gets a newer push.
• 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 per trigger. On Latchkey the same minutes cost up to 58% less than GitHub-hosted, with zero queue time.

Actions used in this workflow