[hardwaresofton]

Hey if you guys are still considering solutions maybe one of the following derivations of Paxos will help:

EPaxos[0] - flexible/minimal quorums + if you're willing to know ops are commutative you can fast-path, and you can flexibly quorum

WPaxos[1] - flexible/minimal quorums + dynamic partitioning via object stealing for spreading writes around

The main benefit of these is of course getting over raft's weakness of the leader being a SPOF.

If you're willing to go with causal consistency there's also CmRDTs (operation/command Replicated Data Types) which are generalizable to "pure operation based CRDTs"[2] which make the merging problem trivial and should in theory boil things down to replication lag while allowing writes at every node.

[0]: https://www.cs.cmu.edu/~dga/papers/epaxos-sosp2013.pdf

[1]: https://cse.buffalo.edu/tech-reports/2017-03.pdf

[2]: https://arxiv.org/pdf/1710.04469.pdf