Cross-Platform Git Migration

Overview

Migrating between Git hosting platforms is straightforward at the Git level — the underlying protocol is the same. The key is transferring all refs (branches, tags, PR/MR metadata).

Core Migration Methods

Method 1: Bare Mirror (Recommended)

# 1. Create a mirror clone from the source
git clone --mirror https://github.com/old-org/repo.git
cd repo.git

# 2. Push to the target platform
git remote set-url origin https://gitlab.com/new-org/repo.git
git push --mirror origin

# 3. Verify
git log --oneline --all

--mirror clones all refs including branches, tags, and notes — the most complete transfer.

Method 2: Direct Push

# If you already have a full local clone
git remote add new-origin https://gitlab.com/new-org/repo.git
git push --all new-origin       # All branches
git push --tags new-origin      # All tags

Method 3: Multi-Platform Sync (Ongoing)

# Configure multiple remotes
git remote add github https://github.com/org/repo.git
git remote add gitlab https://gitlab.com/org/repo.git
git remote add bitbucket https://bitbucket.org/org/repo.git

# Push to all remotes
git push --all github
git push --all gitlab
git push --all bitbucket

Migrating PRs / Merge Requests

PRs/MRs are platform-level metadata, not Git objects — they can't be transferred with git push --mirror.

GitHub → GitHub

# Use GitHub's official migration tool
gh repo migrate <source-repo> --target-owner <target-org>

GitHub → GitLab

1. Create a new project in GitLab
2. Select Import project → GitHub
3. Authorize GitLab to access GitHub
4. Choose the repository to import

GitLab → GitHub

1. Click + → Import repository on GitHub
2. Enter the GitLab repo's Git URL
3. GitHub imports the history automatically

Metadata Migration Map

Post-Migration Checklist

# 1. Verify ref integrity
git for-each-ref --format='%(refname)' | sort

# 2. Check key branches
git branch -a

# 3. Verify tags
git tag -l

# 4. Confirm remote association
git remote -v

Continue Learning

1. migration/svn-to-git — SVN to Git migration
2. migration/hg-to-git — Mercurial to Git migration
3. hosting/platform-comparison — Platform comparison