checks workflow (cashubtc/nutshell)

The checks workflow from cashubtc/nutshell, explained and optimized by Latchkey.

CI health: B - good

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Source: cashubtc/nutshell.github/workflows/checks.ymlLicense MITView source

What it does

This is the checks workflow from the cashubtc/nutshell 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

workflow (.yml)

name: checks

on:
  workflow_call:
    inputs:
      python-version:
        default: "3.12"
        type: string
      poetry-version:
        default: "2.3.2"
        type: string

permissions:
  contents: read

jobs:
  format:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6
      - uses: ./.github/actions/prepare
        with:
          python-version: ${{ inputs.python-version }}
          poetry-version: ${{ inputs.poetry-version }}
      - name: Ruff check
        run: make ruff-check
  mypy:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6
      - uses: ./.github/actions/prepare
        with:
          python-version: ${{ inputs.python-version }}
          poetry-version: ${{ inputs.poetry-version }}
      - name: Setup mypy
        run: yes | poetry run mypy cashu --install-types || true
      - name: Run mypy
        run: poetry run mypy cashu --ignore-missing --check-untyped-defs
  ruff:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v6
      - uses: astral-sh/ruff-action@v3

The same workflow, on Latchkey

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

name: checks
 
on:
  workflow_call:
    inputs:
      python-version:
        default: "3.12"
        type: string
      poetry-version:
        default: "2.3.2"
        type: string
 
permissions:
  contents: read
 
jobs:
  format:
    timeout-minutes: 30
    runs-on: latchkey-small
    steps:
      - uses: actions/checkout@v6
      - uses: ./.github/actions/prepare
        with:
          python-version: ${{ inputs.python-version }}
          poetry-version: ${{ inputs.poetry-version }}
      - name: Ruff check
        run: make ruff-check
  mypy:
    timeout-minutes: 30
    runs-on: latchkey-small
    steps:
      - uses: actions/checkout@v6
      - uses: ./.github/actions/prepare
        with:
          python-version: ${{ inputs.python-version }}
          poetry-version: ${{ inputs.poetry-version }}
      - name: Setup mypy
        run: yes | poetry run mypy cashu --install-types || true
      - name: Run mypy
        run: poetry run mypy cashu --ignore-missing --check-untyped-defs
  ruff:
    timeout-minutes: 30
    runs-on: latchkey-small
    steps:
      - uses: actions/checkout@v6
      - uses: astral-sh/ruff-action@v3

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 3 jobs 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/ruff-action