How to add Github workflows

A quick reference for setting up GitHub Actions workflows.

Structure

Workflows live in .github/workflows/ as YAML files. GitHub picks them up automatically.

name: My Workflow

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - run: echo "Hello from GitHub Actions"

Key Concepts

Triggers (on) — what starts the workflow: push, pull_request, issues, schedule, workflow_dispatch (manual)
Jobs — run in parallel by default; use needs: to chain them
Steps — sequential commands or actions within a job
Actions — reusable steps from the marketplace (e.g., actions/checkout@v4)

Common Triggers

Trigger	When it runs
`push`	Code pushed to a branch
`pull_request`	PR opened, updated, or merged
`issues: [labeled]`	A label is added to an issue
`schedule`	Cron-based (e.g., nightly builds)
`workflow_dispatch`	Manual "Run workflow" button

Permissions

Set fine-grained permissions per job:

permissions:
  contents: write
  issues: write

Tips

Use actions/github-script@v7 to run JS with full GitHub API access
Environment variables pass between steps via core.exportVariable()
Check logs in the repo's Actions tab if something fails