Back in Blog Mode (and Fresh off the GH-200)

I haven’t blogged in a bit, and my home lab has definitely taken a back seat lately. The reason? I’ve been heads-down on certifications.

Just a few weeks ago, I wrapped up the KCNA, and today I officially passed the GitHub Actions (GH-200) exam.

As an architect, I actually enjoy taking exams. Not because I love tests, but because they force accountability. When you work at the architecture level long enough, it’s easy to drift away from the implementation details. Certifications give me a concrete way to validate that I’m still absorbing the material and paying attention to the finer points. The stuff you don’t always hit when you’re doing POCs or designing high-level architectures.

Accountability looks different for everyone, but for me, certs are a reliable forcing function to stay sharp.

Why I’m Sharing This (While It’s Still Fresh)

Since I’m only a few hours removed from hitting that “pass” screen, I figured now was the perfect time to share a few study tips and the cheat sheet I built while prepping.

This is very much a “here’s what worked for me” post.

How I Studied

I like to use multiple sources when learning a new technology. I’ve found that reviewing the same material from two to three different angles really helps reinforce concepts.

My usual pattern looks like this:

• 1 primary reading resource
• 1–2 video resources

For this exam, I reviewed the following:

Reading

• Microsoft’s Offical GH-200 Course Material

Video

• Microsoft’s Offical GH-200 Video Training Course
• Andrew Brown’s GH-200 Course

Practice Exams

For practice exams, I stuck with:

• Microsoft Learning Practice Questions - I actually think these are too easy compare to the exam. This is a good starting place though.
• Exam Pro

The ExamPro videos are free on YouTube, and if you want more structured practice, you can buy their flashcards and 3–4 full practice exams for around $30. For me, that was well worth it.

What to Expect on the Exam

One thing you really need to know about this exam: questions compound knowledge.

You’ll often see an answer that looks like the obvious, quick win. But it’s not the right one.

Slow down. Read carefully. There’s usually an additional constraint, feature, or enterprise-level detail baked into the question that changes the answer.

I also heard from multiple coworkers that the enterprise features caught them off guard. Because I had that heads-up going in, that section didn’t trip me up. If you’re studying, don’t skip enterprise topics. They matter.

Results & Timeline

• Score: 890 / 1000

• Study time: ~2–3 weeks

  • 1–2 hours after work on weekdays
  • A few hands-on labs on the weekends

I already had a background in Azure DevOps, which made the GitHub Actions content easier to digest, but this exam is still very doable if you’re consistent.

The Cheat Sheet

Below is the cheat sheet I put together to review right before the exam.

Domain 1: Author and Maintain Workflows (40%)

Workflow Triggers (Events)

Multiple Events

on: [push, pull_request]

Scheduled (Cron)

on:
  schedule:
    - cron: "0 2 * * 1" # Mondays at 2am UTC

Manual Trigger

on:
  workflow_dispatch:
    inputs:
      environment:
        required: true

Webhook Events

• check_run
• check_suite
• deployment
• deployment_status
• Used for CI/CD integrations and chained workflows

Workflow Components

Component	Description
Workflow	YAML file in .github/workflows/
Job	Group of steps, runs on one runner
Step	Action or shell command
Action	Reusable unit (JS, Docker, composite)
Run	One execution of a workflow

Workflow Syntax Basics

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - run: npm install

Key Rules

• YAML indentation matters
• steps must be under jobs.<job_id>
• Each job runs on a single runner

Conditional Logic

Step Condition

if: github.ref == 'refs/heads/main'

Job Condition

if: success()

Dependent Jobs

jobs:
  build:
    runs-on: ubuntu-latest

  deploy:
    needs: build
    runs-on: ubuntu-latest

Runners

GitHub-hosted

• Short-lived
• No custom software
• Best for standard CI

Self-hosted

• Custom tools
• Network access
• Long-running jobs

Runner Labels

runs-on: [self-hosted, linux, custom-software]

Secrets & Environment Variables

Encrypted Secrets

env:
  API_KEY: $

Default Environment Variables

• GITHUB_REPOSITORY
• GITHUB_REF
• GITHUB_SHA
• GITHUB_RUN_ID

Custom Env Vars

• Workflow-level: env:
• Job-level: jobs.<job>.env
• Step-level: steps[].env

GITHUB_TOKEN

Use when:

• Creating issues
• Publishing packages
• Pushing to repos
• Authenticating to GitHub APIs

env:
  GITHUB_TOKEN: $

Workflow Commands

Set Environment Variable

echo "MY_VAR=value" >> $GITHUB_ENV

Set Output

echo "result=success" >> $GITHUB_OUTPUT

Publishing & Deployment

GitHub Packages / GHCR

• Authenticate
• Build artifact/image
• Push to registry

Service Containers

services:
  postgres:
    image: postgres:15

CodeQL

- uses: github/codeql-action/analyze@v3

Releases

• Create GitHub release
• Upload artifacts
• Deploy to cloud provider

Domain 2: Consume Workflows (20%)

Interpreting Workflow Effects

• Check commits, PRs, releases, issues
• Inspect triggered event via run metadata
• Read workflow YAML to infer behavior

Diagnosing Failures

UI

• Actions tab → Workflow → Job → Step logs

REST API

• List workflow runs
• Download logs and artifacts

Debugging

Enable Step Debug

env:
  ACTIONS_STEP_DEBUG: true

Data Between Jobs

Artifacts

- uses: actions/upload-artifact@v4

Outputs

outputs:
  version: $

Caching

- uses: actions/cache@v4
  with:
    path: ~/.npm
    key: npm-${{ hashFiles('package-lock.json') }}

Workflow Management

• Add status badge from Actions UI

• Delete vs Disable:

  • Disable: keeps history
  • Delete: removes file + history

• Environment protections:

  • Required reviewers
  • Deployment gates
• Matrix builds:

strategy:
  matrix:
    node: [18, 20]

Domain 3: Author and Maintain Actions (25%)

Action Types

Type	Use Case
JavaScript	Fast, reusable, Node-based
Docker	Heavy dependencies
Composite	Glue steps together

Action Structure

action.yml
index.js
Dockerfile

Metadata

• name
• inputs
• runs
• outputs

Troubleshooting Actions

JavaScript

• Check Node version
• Review logs
• Validate action.yml

Docker

• Dockerfile errors
• ENTRYPOINT issues
• Permissions

Workflow Commands in Actions

• Exit codes control success/failure
• core.setFailed()
• process.exit(1)

Domain 4: Manage GitHub Actions in the Enterprise (15%)

Reuse & Distribution

• Reusable workflows (workflow_call)
• Centralized action repos
• Naming conventions
• Version pinning

Access Control

• Organization policies
• Allow/deny action sources
• Control who can use which actions

Runners at Scale

GitHub-hosted

• Subject to IP allow lists

Self-hosted

• Custom networking
• Proxies
• Labels
• Groups for access control

Runner Management

• Group runners by purpose
• Move runners between groups
• Monitor _diag logs
• Update runner binaries regularly

Secrets in the Enterprise

Scope	Use
Organization	Shared across repos
Repository	Repo-specific
Environment	Protected deployments

Access via:

${{ secrets.MY_SECRET }}