Git rebase without fear: a practical guide

Rebase has a scary reputation, mostly because people first meet it while fixing a mess. Used deliberately, it is just a way to replay your commits on top of a newer base. This guide covers the three jobs you will actually use it for.

What rebase does

Say you branched from main last week, and main has moved on since. A merge ties the two histories together with an extra merge commit. A rebase lifts your commits and replays them one by one on top of the latest main, as if you had started today.

Your changes are the same. The history is a straight line.

Job 1: bring your branch up to date

git switch my-feature
git fetch origin
git rebase origin/main

If a commit conflicts, Git pauses and tells you which file. Fix the file, then continue:

git add path/to/file
git rebase --continue

If it turns into a tangle, you can always back out and return to where you started:

git rebase --abort

Job 2: tidy your commits before review

Interactive rebase lets you clean up work-in-progress commits. To edit your last four commits:

git rebase -i HEAD~4

Git opens a list. Change the word at the start of each line to say what you want:

Command	What it does
`pick`	Keep the commit as it is
`reword`	Keep the changes, edit the message
`squash`	Merge into the previous commit and combine messages
`fixup`	Merge into the previous commit and discard the message
`drop`	Remove the commit entirely

A typical cleanup turns "WIP", "fix typo" and "actually fix it" into one commit with a proper message.

Job 3: publish the rewritten branch

Rebasing changes commit hashes, so Git will refuse a normal push. Use the safer force option:

git push --force-with-lease

Unlike --force, this fails if someone else pushed to the branch since you last fetched, so you cannot overwrite their work by accident.

Your safety net

Even a bad rebase is recoverable. Git remembers where your branch pointed before, and git reflog lists it:

git reflog
git reset --hard HEAD@{5}

Find the entry from before the rebase, and reset to it. Nothing is lost until Git garbage-collects it, which takes weeks.

A simple habit

Rebase onto main before you open a pull request, squash the noise, and push with --force-with-lease. Reviewers will read a clean story, and you will stop dreading the command.