gitbrute brute-forces a pair of author+committer timestamps such that the resulting git commit has your desired prefix. It will find the most recent time that satisfies your prefix. Shorter prefixes match more quickly, of course. The author & committer timestamp are not kept in sync. Example: https://github.com/bradfitz/deadbeef Usage: go run gitbrute.go --prefix 000000 This amends the last commit of the current repository.