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Rewrite git history safely with git filter-repo. Use when removing secrets or sensitive files from commits, rewriting author/committer emails across history, de-duplicating doubled commits, or any commit-level surgery.
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| name | git-history-surgery |
| description | Rewrite git history safely with git filter-repo. Use when removing secrets or sensitive files from commits, rewriting author/committer emails across history, de-duplicating doubled commits, or any commit-level surgery. |
Use git filter-repo — not delete-and-recreate. Deleting the repo loses
settings, branch protections, access controls, and issue/PR history.
git filter-repo \
--path path/to/sensitive-file \
--invert-paths \
--force
git filter-repo removes the remote as a safety measure — re-add it after:
git remote add origin <url>
git push --force --set-upstream origin main
Teammates must then re-clone or hard reset:
git fetch --all && git reset --hard origin/main
Known issue: git filter-repo crashes if any git config value contains a
literal newline (e.g. a multi-line alias). Workaround:
GIT_CONFIG_NOSYSTEM=1 HOME=/dev/null git filter-repo --path ... --invert-paths --force
Use git filter-repo --mailmap for pure identity rewrites (wrong author/email):
# mailmap format: canonical <right@email.com> <wrong@email.com>
cat > mailmap << 'EOF'
USER NAME <USER EMAIL> <wrong.name@corp.com>
EOF
GIT_CONFIG_NOSYSTEM=1 HOME=/dev/null git filter-repo --mailmap mailmap --force
git remote add origin <url>
git config --local user.name "USER NAME"
git config --local user.email "USER EMAIL"
Choose tool based on whether commits are unique:
--mailmap.
Filter-repo preserves graph topology and rewrites identity metadata only.git commit-tree replay to de-duplicate.
Filter-repo cannot collapse duplicate lineages.How to check before choosing:
# Count distinct trees for bad-email commits — must equal commit count for mailmap to be safe
git log --all --format='%T %ae' | grep 'corp\.com' | awk '{print $1}' | sort -u | wc -l
Verification after mailmap rewrite (all must pass before force-push):
# 1. No bad identities remain (must print nothing):
git log --all --format='%ae%n%ce' | grep -iE 'corp\.com'
# 2. Good bots preserved (count should be unchanged):
git log --all --format='%ce' | grep -c 'noreply@github\.com'
# 3. Commit count unchanged:
git rev-list --all --count
Always bundle-backup first and keep it until the force-push is confirmed:
git bundle create backup.bundle --all