Rebase Safely

1. Backup first — git branch backup/<name> before any rewrite. Free undo.
2. Rebase onto the latest base: git fetch; git rebase origin/main.
3. Resolve conflicts one commit at a time. Test after the rebase, not just that it "completed".
4. Never rewrite shared history — if others pulled the branch, rebasing it forces them into pain. Rewrite only your own un-pushed/un-shared commits.
5. Push with --force-with-lease, never bare --force (lease refuses if someone else pushed). If anything goes sideways: git reflog finds the pre-rebase state; git reset --hard backup/<name> restores it.