Apply Modern Development Practices
This skill area is 10–15% of the exam. It covers automation and AI tooling: GitHub Actions, GitHub Copilot (including Copilot agents, Agent Mode, and multi-model support), the Copilot plans, GitHub Codespaces and dev containers, and the github.dev browser editor.
GitHub Actions
GitHub Actions is GitHub's built-in automation and CI/CD platform. It runs workflows in response to events in your repository.
Core Concepts & Vocabulary
| Term | Meaning |
|---|---|
| Workflow | An automated process defined in a YAML file under .github/workflows/. |
| Event | An activity that triggers a workflow (e.g. push, pull_request, schedule, manual workflow_dispatch). |
| Job | A set of steps that run on the same runner; jobs run in parallel by default and can depend on each other. |
| Step | An individual task — either a shell command or an action. |
| Action | A reusable unit of code (yours or from the Marketplace) used as a step. |
| Runner | The server that executes a job — GitHub-hosted (Linux/Windows/macOS) or self-hosted. |
Beyond CI/CD (build, test, deploy), Actions automates any workflow: labeling issues, greeting first-time contributors, running scheduled tasks, and publishing packages. Workflows are event-driven and written in YAML.
GitHub Copilot
GitHub Copilot is an AI pair programmer that provides AI-powered code suggestions and chat assistance in your editor, on GitHub.com, in the CLI, and in the mobile app.
What Copilot Can Do
- Code completion — real-time inline (ghost-text) suggestions as you type.
- Copilot Chat — natural-language help to explain code, fix bugs, generate tests, and answer questions in context.
- Multi-model support — choose among multiple underlying AI models for different tasks.
- CLI, PR summaries, and code review assistance across the GitHub platform.
Copilot Agents & Agent Mode
- Agent Mode lets Copilot act more autonomously — it can plan a task, edit multiple files, run commands/tools, and iterate toward a goal, checking its own results.
- Copilot coding agent can be assigned work (e.g. an issue) and open a pull request with a proposed implementation for you to review.
- You remain accountable for reviewing and validating any AI-generated code before it is merged.
Copilot for Individuals, Business & Enterprise
| Plan | Who it's for & what it adds |
|---|---|
| Copilot Free | A limited free tier for individuals to try completions and chat with monthly caps. |
| Copilot Pro / Pro+ (Individuals) | Full personal plan for a single developer — unlimited completions and chat, model choice. Free for verified students, teachers, and popular open-source maintainers. |
| Copilot Business | For organizations: adds organization-wide license and policy management, content exclusions, and audit — admins control who has access and how it's used. |
| Copilot Enterprise | Everything in Business plus deep GitHub.com integration — Copilot knowledge bases, PR summaries, and org-wide capabilities for large enterprises. |
The key distinction: Individual plans cover one developer; Business adds centralized policy and license management for teams; Enterprise adds enterprise-grade integration across GitHub.com (knowledge bases, org-wide controls). Match the plan to the org's governance need.
GitHub Codespaces & Dev Containers
- Codespaces is a cloud-hosted development environment — a full VS Code (browser or desktop) backed by a container running on GitHub's infrastructure.
- It gives you a ready-to-code environment in minutes with no local setup, accessible from anywhere.
- Customize it with a dev container (
.devcontainer/devcontainer.json) that defines the OS image, tools, extensions, settings, and post-create commands — so every contributor gets an identical, reproducible environment. - Codespaces has a free monthly usage allowance for personal accounts; beyond that it is billed by compute and storage.
github.dev vs. Codespaces
Both edit code in the browser, but they are very different tools. Knowing when to use which is exam-relevant.
| github.dev | Codespaces | |
|---|---|---|
| How to open | Press . in a repo, or change github.com to github.dev | Code → Codespaces → Create codespace |
| Compute / terminal | None — lightweight editor only, no terminal, no build/run | Full cloud VM with terminal; can build, run, test, debug |
| Cost | Free | Free monthly allowance, then billed by usage |
| Best for | Quick edits, small changes, browsing/committing files | Real development that needs to compile, run, and test code |
github.dev = a fast, free, lightweight editor (no compute). Codespaces = a full cloud dev environment that can actually run your code. Need to just tweak a file? github.dev. Need to build and test? Codespaces.
Study Resources
- GitHub Actions Documentation Workflows, events, jobs, runners, and the Actions Marketplace.
- GitHub Copilot Documentation Features, agents, plans, and configuration.
- Copilot Plans (GitHub Docs) Compares Free, Pro, Business, and Enterprise.
- GitHub Codespaces Documentation Creating, customizing, and using cloud dev environments and dev containers.
- GitHub Foundations — Part 2 (Microsoft Learn) Modules on Actions, Copilot, and Codespaces.