Keybase started out with an identity system because it was the key foundational module to create their entire e2e encrypted software system. After the user sys

Keybase started out with an identity system because it was the key foundational module to create their entire e2e encrypted software system. After the user system, they created a network filesystem, which their git system is based upon, and I'm guessing it's also something their team chat system uses too. The entire groups system is also based on their user system. It looked like they were building out a dependency tree bit by bit.