So many paragraphs in the beginning, just to finally read: > Do we want to migrate to another hash? Yes. Wouldn't all that time trying to explain away the SHA

So many paragraphs in the beginning, just to finally read: > Do we want to migrate to another hash? Yes. Wouldn't all that time trying to explain away the SHA-1 issues be better spent on developing a safe transition plan? Work on this could have started long ago, and if it would have started, going from SHA-256 to SHA-512 to SHA-3 to ... would be a no-brainer by now. In the simplest case, ensure that all newly created git repositories work woth SHA-256 by default (or SHA-512, or whatever), and switch back to SHA-1 for old repositories. In the more advanced case, provide the possibility for existing repositories to have multiple hash values (SHA-1, SHA-256) for every blob/commit, then phasing out client support for old hashes as time goes on. When some SHA-1 collision happens, those who use newer git versions would notice and keep having a consistent repository. If all those different browsers and web servers were able to coordinate a SSL/TLS hash transition SHA-1 to SHA-256, then a protocol like git with roughly 2 widespread implementations should be able to do that, too.