The Branch

Why this matters

Branches are the developer's sandboxing tool. Every experiment, every risky change, every unfinished feature gets its own branch — a parallel version of the codebase where nothing affects main until you explicitly merge it. This is the safety net that makes fearless development possible. In Module 5, Claude Code will create branches automatically before making changes. Understanding branches now means you will understand what Claude Code is doing and why.

How to do it

1. 1

   Create a feature branch

   git checkout -b feature/my-experiment (or in VS Code Source Control, click the branch name at the bottom and choose "Create new branch")

2. 2

   Make 2–3 changes on the branch

   Any changes — modify some text, change a color, add a small element. Commit each change.

3. 3

   Merge the branch into main

   git checkout main → git merge feature/my-experiment — your changes are now in main.

4. 4

   Create a conflict and resolve it with AI help

   On main, change the same line you changed on the branch. Then try to merge — you'll get a conflict. Use the conflict resolution prompt to understand and fix it.

The prompt

I have a merge conflict in my git repository. Here is the conflict section in my file:

[PASTE THE CONFLICT SECTION — it will look like <<<<<<< HEAD ... ======= ... >>>>>>> feature-branch]

Please:
1. Explain what this conflict means in plain language
2. Tell me what each version contains (HEAD version and the branch version)
3. Recommend which version to keep, or how to combine them
4. Show me exactly what the file should look like after the conflict is resolved

Success criteria

• ✓You created a feature branch, made changes, and merged it to main
• ✓You created a merge conflict intentionally and resolved it
• ✓You can explain what conflict markers mean
• ✓You understand why branches make risky work safe

Common mistakes