Electron Rebuild Testing workflow (MagicMirrorOrg/MagicMirror)

The Electron Rebuild Testing workflow from MagicMirrorOrg/MagicMirror, explained and optimized by Latchkey.

What it does

This is the Electron Rebuild Testing workflow from the MagicMirrorOrg/MagicMirror 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: "Electron Rebuild Testing"

permissions:
  contents: read

on: [pull_request]

jobs:
  rebuild:
    name: Run electron-rebuild
    runs-on: ubuntu-slim
    strategy:
      matrix:
        node-version: [22.x, 24.x, 26.x]
    steps:
      - name: Checkout code
        uses: actions/checkout@v7
      - name: "Use Node.js ${{ matrix.node-version }}"
        uses: actions/setup-node@v6
        with:
          node-version: ${{ matrix.node-version }}
          check-latest: true
      - name: Install MagicMirror
        run: node --run install-mm
      - name: Install @electron/rebuild
        run: npm install @electron/rebuild
      - name: Install test library (serialport) to be rebuilt
        run: npm install serialport
      - name: Run electron-rebuild
        run: npx electron-rebuild
        continue-on-error: false

The same workflow, on Latchkey

Estimated ~20% faster on cache hits, plus fewer wasted runs and a safer supply chain. Added and changed lines are highlighted.

name: "Electron Rebuild Testing"
 
permissions:
  contents: read
 
on: [pull_request]
 
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true
 
jobs:
  rebuild:
    timeout-minutes: 30
    name: Run electron-rebuild
    runs-on: ubuntu-slim
    strategy:
      matrix:
        node-version: [22.x, 24.x, 26.x]
    steps:
      - name: Checkout code
        uses: actions/checkout@v7
      - name: "Use Node.js ${{ matrix.node-version }}"
        uses: actions/setup-node@v6
        with:
          cache: 'npm'
          node-version: ${{ matrix.node-version }}
          check-latest: true
      - name: Install MagicMirror
        run: node --run install-mm
      - name: Install @electron/rebuild
        run: npm install @electron/rebuild
      - name: Install test library (serialport) to be rebuilt
        run: npm install serialport
      - name: Run electron-rebuild
        run: npx electron-rebuild
        continue-on-error: false
 

What changed

• Cancel superseded runs when a branch or PR gets a newer push.
• Cache dependency installs on the setup step so they are served from cache.
• Add a job timeout so a hung step cannot burn hours of runner time.

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