@yangzh we do not have plans on building a distributed key-value store for now. We’re focussed on building a distributed GraphQL database.
Distributed badger can be a nice project in which you integrate raft with Badger DB.
However, there is an open source distributed version of badger DB GitHub - mosuka/cete: Cete is a distributed key value store server written in Go built on top of BadgerDB. written in Go.