GitHub Actions is a powerful CI/CD (Continuous Integration/Continuous Deployment) feature built directly into GitHub. It allows you to automate workflows based on events in your repository.

What are GitHub Actions?

GitHub Actions let you:

• Run tests automatically when you push code
• Build and deploy your application
• Automate repetitive tasks
• Respond to issues and pull requests

Example: Deploy to Fly.io

Fly.io is a very cool cloud hosting platform but one thing I miss is automatic deploy when I do a GitHub commit, as the services are not linked to GitHub.

To add CD (Continuous Deployment) to Fly.io we need to create a GitHub action.

I suppose you already have a Fly app running and a fly.toml file in your repo.

In your project repo, create .github/workflows/fly.yml:

name: Fly Deploy
on:
  push:
    branches:
      - main
jobs:
  deploy:
    name: Deploy app
    runs-on: ubuntu-latest
    concurrency: deploy-group
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
        with:
          node-version: 20
      - uses: superfly/flyctl-actions/setup-flyctl@master
      - run: flyctl deploy --remote-only
        env:
          FLY_API_TOKEN: ${{ secrets.FLY_API_TOKEN }}

Make sure you set the name of the branch you want to deploy (in this example, I deploy the main branch).

Setting up secrets

In your terminal run:

fly tokens create deploy -x 999999h

to generate the Fly token and add it to the actions secrets in GitHub:

Call the secret FLY_API_TOKEN and enter the value you got from fly tokens...:

Running the action

Push to GitHub, you’ll see your action running:

You can see all the details of the action by clicking it:

In the jobs tab you can see what happened in the build:

Go on Fly, you’ll see the action was successful:

And the app is deployed on every commit.

All your deploys also have a “check” now to indicate that the action was successful (or not):

Common GitHub Actions patterns

Run tests on push

name: Tests
on: [push, pull_request]
jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
        with:
          node-version: 20
      - run: npm ci
      - run: npm test

Build and deploy to Netlify

name: Deploy to Netlify
on:
  push:
    branches:
      - main
jobs:
  deploy:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
        with:
          node-version: 20
      - run: npm ci
      - run: npm run build
      - uses: nwtgck/actions-netlify@v2
        with:
          publish-dir: './dist'
          production-deploy: true
        env:
          NETLIFY_AUTH_TOKEN: ${{ secrets.NETLIFY_AUTH_TOKEN }}
          NETLIFY_SITE_ID: ${{ secrets.NETLIFY_SITE_ID }}

Key concepts

• Workflows: YAML files in .github/workflows/ that define automation
• Events: Triggers like push, pull_request, schedule, etc.
• Jobs: Groups of steps that run on the same runner
• Steps: Individual tasks that run commands or actions
• Actions: Reusable units of code (like actions/checkout@v4)
• Secrets: Encrypted environment variables for sensitive data

Lessons in this unit:

0:	Introduction
1:	Setting up Git and GitHub from scratch
2:	Authentication methods
3:	Making your first pull request
4:	▶︎ GitHub Actions for CI/CD