Flow check, Lint and Tests workflow (graphql/dataloader)

The Flow check, Lint and Tests workflow from graphql/dataloader, explained and optimized by Latchkey.

What it does

This is the Flow check, Lint and Tests workflow from the graphql/dataloader 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: Flow check, Lint and Tests 

on: push

jobs:
  validation:
    name: Testing on Node ${{ matrix.node-version }}
    runs-on: ubuntu-latest
    strategy:
      matrix:
        node-version: [18, 20, 22]
    steps:
      - name: Checkout Repository
        uses: actions/checkout@v4

      - name: Use Node ${{ matrix.node-version }}
        uses: actions/setup-node@v4
        with:
          node-version: ${{ matrix.node-version }}
          cache: 'yarn'

      - name: Install Dependencies using Yarn
        run: yarn --ignore-engines

      - name: Tests
        run: yarn test:ci 

      - name: Upload coverage to Codecov
        uses: codecov/codecov-action@v4
        env:
          CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
        with:
          fail_ci_if_error: true

The same workflow, on Latchkey

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

name: Flow check, Lint and Tests 
 
on: push
 
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true
 
jobs:
  validation:
    timeout-minutes: 30
    name: Testing on Node ${{ matrix.node-version }}
    runs-on: latchkey-small
    strategy:
      matrix:
        node-version: [18, 20, 22]
    steps:
      - name: Checkout Repository
        uses: actions/checkout@v4
 
      - name: Use Node ${{ matrix.node-version }}
        uses: actions/setup-node@v4
        with:
          node-version: ${{ matrix.node-version }}
          cache: 'yarn'
 
      - name: Install Dependencies using Yarn
        run: yarn --ignore-engines
 
      - name: Tests
        run: yarn test:ci 
 
      - name: Upload coverage to Codecov
        uses: codecov/codecov-action@v4
        env:
          CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
        with:
          fail_ci_if_error: true
 

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.

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:

• Dependency installs

This workflow runs 1 job (3 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