Interactive Rebase

Quick Summary

Interactive rebase (git rebase -i) lets you rewrite history commit-by-commit. You can reorder commits, squash messy "WIP" commits into one clean commit, edit commit messages, split commits, or drop commits entirely. It's the tool for polishing your branch before merging.

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Starting Interactive Rebase

# Rebase last N commits
git rebase -i HEAD~4

# Rebase onto a specific branch
git rebase -i main

Git opens your editor with a list of commits:

pick a1b2c3d feat: add login form
pick b2c3d4e fix: typo in login
pick c3d4e5f WIP: debugging
pick d4e5f6a feat: add validation

# Commands:
# p, pick   = use commit as-is
# r, reword = edit the commit message
# e, edit   = pause to amend the commit
# s, squash = merge into previous commit (keep message)
# f, fixup  = merge into previous commit (discard message)
# d, drop   = delete the commit
# x, exec   = run a shell command

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Common Operations

Squash Multiple Commits

pick a1b2c3d feat: add login form
fixup b2c3d4e fix: typo in login        # ← merge into above, discard message
fixup c3d4e5f WIP: debugging            # ← merge into above, discard message
pick d4e5f6a feat: add validation

Result: 4 commits → 2 clean commits

Reorder Commits

pick d4e5f6a feat: add validation        # ← moved up
pick a1b2c3d feat: add login form

Edit a Commit Message

reword a1b2c3d feat: add login form      # ← Git will prompt for new message
pick d4e5f6a feat: add validation

Split a Commit

edit a1b2c3d feat: add login + validation  # ← pause here

When Git pauses:

# Undo the commit but keep changes staged
git reset HEAD~1

# Stage and commit separately
git add src/login.js
git commit -m "feat: add login form"

git add src/validation.js
git commit -m "feat: add validation"

# Continue the rebase
git rebase --continue

Drop a Commit

pick a1b2c3d feat: add login form
drop c3d4e5f WIP: debugging              # ← deleted entirely
pick d4e5f6a feat: add validation

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Autosquash (Fixup Workflow)

The fastest way to fix previous commits:

# Make the fix and commit with --fixup
git commit --fixup=a1b2c3d

# Later, autosquash (auto-reorder and squash fixups)
git rebase -i --autosquash main

Git automatically marks fixup commits and places them next to their targets.

Enable autosquash by default:

git config --global rebase.autosquash true

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Safety Rules

Golden Rule

Never rebase commits that have been pushed to a shared branch. Rebasing changes commit hashes, which breaks other developers' history.

Safe: Rebasing your local, unpushed feature branch
Dangerous: Rebasing main or any shared branch

Scenario	Safe to Rebase?
Local commits, never pushed	✅ Always safe
Your branch, only you use it	⚠️ Use --force-with-lease to push
Shared branch with other devs	❌ Never
Already-merged commits	❌ Never

Recovery

# Abort a rebase in progress
git rebase --abort

# Find commits before the rebase (in reflog)
git reflog
# Restore: git reset --hard HEAD@{N}

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Best Practices

• Squash "fix typo" and "WIP" commits before creating a PR
• Use --fixup + --autosquash for the cleanest workflow
• Keep commit scopes small — easier to reorder and squash
• Always rebase your feature branch onto main before merging
• Never rebase shared history

What's Next

1. Cherry-Pick & Bisect — Select specific commits and find bug introductions
2. Hooks & Automation — Automate tasks with Git hooks