Steam Archive Manager -

– Plug in the Vault, click “Restore” in SAM. It verified file integrity (no re-download) and symlinked everything back. Restore time: 8 minutes vs. 5 hours to re-download.

An open-source tool that allows you to drag and drop games between different drives and backup folders seamlessly. It is ideal for users who want to "archive" games to a slow HDD while keeping active titles on an SSD. steam archive manager

Archives are renamed to include the Build ID to prevent collisions. – Plug in the Vault, click “Restore” in SAM