01beginner
First Commit
Put the project under Git with a single commit holding the site, keep debug.log out of history for good, and leave a clean working tree.
- git-init
- staging
- commits
- gitignore
Challenges
Real-world Git problems. No step-by-step instructions: just a scenario, a mission and a repository that needs you.
Basics
Repositories, staging and commits.
Branching
Branches, HEAD and moving between them.
02intermediate
Wrong Branch
Move both login commits onto a new branch called feature/login, and put main back where it was before you started.
- branches
- reset
03intermediate
Detached HEAD
Make sure both commits survive on a branch called fix/rounding, then get back to main.
- detached-head
- branches
- head
04intermediate
Uncommitted Changes
Merge hotfix/rounding into release, then get back to main with your unfinished price work exactly as it was, not committed, and nothing left stashed.
- stash
- branches
- merging
Conflicts
When two changes collide.
05intermediate
Merge Conflict
Bring release/2.0 into main with a merge commit. Keep the new host and the longer timeout, decide what happens to the setup guide, and finish on main with nothing left uncommitted.
- merge-conflicts
- merging
06advanced
Resolve a Rebase Conflict
Put feature/retries on top of the current main while keeping the new region and the higher retry count in src/settings.js. Finish on the feature branch with no conflict or local change.
- rebase
- conflicts
- conflict-resolution
Recovery
Undoing mistakes and finding lost work.
07beginner
Undo Last Commit
Rewrite the last commit so that config.js is committed but secrets.env never was, ignore secrets.env from now on, and keep history to two commits.
- reset
- gitignore
- history
08intermediate
Lost Commit
Bring feature/payments back with both of its commits, without touching main.
- reflog
- branches
- recovery
09intermediate
Recover Stashed Work
Visit main, then return to feature/invoice-notes with the invoice edit still modified and uncommitted, your launch draft restored as an untracked file, and no work left in the stash.
- stash
- branches
- untracked-files
10intermediate
Revert a Shared Change
Turn the unfinished checkout back off while preserving the faulty commit, the earlier export work, and the shared history. Leave main clean.
- revert
- shared-history
- recovery
11intermediate
Recover a Deleted File
Restore the deployment checklist with its original contents, preserve the newer health endpoint work, and leave the restoration recorded on a clean main branch.
- restore
- history
- recovery
History
Copying and reshaping commits.
12intermediate
Cherry-Pick One Fix
Get the crash fix into release/1.4 without bringing any of main's new features along.
- cherry-pick
- branches
13advanced
Clean Up History
Replace the four messy commits with a single commit called Add search, keeping the final code exactly as it is.
- reset
- history
- squash
14advanced
Rebase a Feature Branch
Put both notification commits directly on top of the current main, keep main exactly where it is, and finish on feature/notifications with a clean working tree.
- rebase
- branches
- history
15advanced
Split a Mixed Commit
Replace the mixed commit with Add analytics service, changing only the service file, followed by Document analytics service, changing only the guide. Preserve both files and finish clean.
- reset
- staging
- history
Advanced
Several problems at once.
16advanced
Repository Recovery
Restore main with Add invoice PDFs, bring back feature/reports with its commit, commit the stashed dark-mode work on main as Add dark mode, and leave the stash empty and the working tree clean.
- reflog
- stash
- reset
- branches
17advanced
Repair Reset Branches
Restore each branch to its own completed commit without moving the other branch, then finish on feature/catalog with a clean working tree and both pieces of work reachable.
- reflog
- reset
- branches
- recovery