Skip to content
Latchkey

Crossplatform workflow (tough-dev-school/education-backend)

The Crossplatform workflow from tough-dev-school/education-backend, explained and optimized by Latchkey.

B

CI health: B - good

Point runs-on at Latchkey and get job timeouts, SHA-pinned actions, self-healing for flaky steps, and up to 58% lower cost, applied automatically.

Grade your own workflow free or run it on Latchkey →
Source: tough-dev-school/education-backend.github/workflows/crossplatform.ymlLicense MITView source

What it does

This is the Crossplatform workflow from the tough-dev-school/education-backend 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: Crossplatform

on:
  schedule:
    - cron: '30 4 * * *'
  workflow_dispatch:

jobs:
  lint:
    runs-on: ubuntu-24.04
    steps:
      - name: checkout
        uses: actions/checkout@v6

      - name: build
        uses: ./.github/actions/build

      - name: lint
        run: make lint

  test:
    needs: lint
    runs-on: ubuntu-24.04
    services:
      postgres:
        image: postgres:15-alpine
        env:
          POSTGRES_PASSWORD: secret
        options: >-
          --health-cmd pg_isready
          --health-interval 10s
          --health-timeout 5s
          --health-retries 5
        ports:
          - 5432:5432
      redis:
        image: redis:6.2.20-alpine
        ports:
          - 6379:6379

    steps:
      - name: checkout
        uses: actions/checkout@v6

      - name: build
        uses: ./.github/actions/build

      - name: install locale stuff
        run: |
          sudo apt-get update
          sudo apt-get --no-install-recommends install -y locales-all gettext

      - name: test
        env:
          DATABASE_URL: postgres://postgres:secret@localhost:5432/postgres
          REDISCLOUD_URL: redis://localhost:6379/5
        run: make test

  build-docker-image:
    needs: test
    runs-on: ubuntu-24.04
    steps:
      - name: checkout
        uses: actions/checkout@v6

      - name: build
        uses: ./.github/actions/build

      - name: set up qemu
        uses: docker/setup-qemu-action@v3

      - name: set up buildx
        uses: docker/setup-buildx-action@v3

      - name: generate image identifier
        id: image
        uses: ASzc/change-string-case-action@v6
        with:
          string: ${{ github.repository_owner }}

      - name: login to ghcr
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.repository_owner }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: build dev image
        uses: docker/build-push-action@v6
        with:
          context: .
          target: web
          push: true
          platforms: linux/amd64,linux/arm64
          tags: |
            ghcr.io/${{ steps.image.outputs.lowercase }}/dev-backend:${{ github.sha }}
            ghcr.io/${{ steps.image.outputs.lowercase }}/dev-backend:${{ github.ref_name }}
            ${{ github.ref == 'refs/heads/master' && 'ghcr.io/tough-dev-school/dev-backend:latest' || '' }}
          build-args: |
            PYTHON_VERSION=${{ env.python-version }}
            RELEASE=${{ github.sha }}
          cache-from: type=gha
          cache-to: type=gha,mode=max

The same workflow, on Latchkey

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

name: Crossplatform
 
on:
  schedule:
    - cron: '30 4 * * *'
  workflow_dispatch:
 
jobs:
  lint:
    timeout-minutes: 30
    runs-on: latchkey-small
    steps:
      - name: checkout
        uses: actions/checkout@v6
 
      - name: build
        uses: ./.github/actions/build
 
      - name: lint
        run: make lint
 
  test:
    timeout-minutes: 30
    needs: lint
    runs-on: latchkey-small
    services:
      postgres:
        image: postgres:15-alpine
        env:
          POSTGRES_PASSWORD: secret
        options: >-
          --health-cmd pg_isready
          --health-interval 10s
          --health-timeout 5s
          --health-retries 5
        ports:
          - 5432:5432
      redis:
        image: redis:6.2.20-alpine
        ports:
          - 6379:6379
 
    steps:
      - name: checkout
        uses: actions/checkout@v6
 
      - name: build
        uses: ./.github/actions/build
 
      - name: install locale stuff
        run: |
          sudo apt-get update
          sudo apt-get --no-install-recommends install -y locales-all gettext
 
      - name: test
        env:
          DATABASE_URL: postgres://postgres:secret@localhost:5432/postgres
          REDISCLOUD_URL: redis://localhost:6379/5
        run: make test
 
  build-docker-image:
    timeout-minutes: 30
    needs: test
    runs-on: latchkey-small
    steps:
      - name: checkout
        uses: actions/checkout@v6
 
      - name: build
        uses: ./.github/actions/build
 
      - name: set up qemu
        uses: docker/setup-qemu-action@v3
 
      - name: set up buildx
        uses: docker/setup-buildx-action@v3
 
      - name: generate image identifier
        id: image
        uses: ASzc/change-string-case-action@v6
        with:
          string: ${{ github.repository_owner }}
 
      - name: login to ghcr
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.repository_owner }}
          password: ${{ secrets.GITHUB_TOKEN }}
 
      - name: build dev image
        uses: docker/build-push-action@v6
        with:
          context: .
          target: web
          push: true
          platforms: linux/amd64,linux/arm64
          tags: |
            ghcr.io/${{ steps.image.outputs.lowercase }}/dev-backend:${{ github.sha }}
            ghcr.io/${{ steps.image.outputs.lowercase }}/dev-backend:${{ github.ref_name }}
            ${{ github.ref == 'refs/heads/master' && 'ghcr.io/tough-dev-school/dev-backend:latest' || '' }}
          build-args: |
            PYTHON_VERSION=${{ env.python-version }}
            RELEASE=${{ github.sha }}
          cache-from: type=gha
          cache-to: type=gha,mode=max
 

What changed

5 third-party actions are referenced by a movable tag. Pin them to the commit SHA (Latchkey resolves and applies this automatically) so a repointed tag cannot change what runs.

What Latchkey heals here

This workflow has steps that commonly fail on transient issues (network, registries, flaky browsers). On Latchkey managed runners they are detected, retried, and self-healed instead of failing your build:

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