OpenHub (formerly Ohloh) tries, or tried, to do this. Seems like it’s not getting a lot of love lately but perhaps you can learn from it.
One useful feature is the ability to coalesce different identities. For example, I've released libraries on my personal accounts as well as through work. For a while I used to link there from my personal site since it nearly summarized that I’d made N thousand commits to OSS. But I stopped. I’m not really sure what the point is for me.
https://openhub.net/accounts/neilk
If it’s bragging rights, we have Github stars. Effectively (and sadly) open source is a resume building tool nowadays, so maybe that?
What use cases do you see?