In Local-First software, we typically build applications on top of replicated data types (RDTs). Locally computed results are persisted in RDTs, which are then synchronized to achieve eventual consistency.

Recent research, however, explores implementing applications as RDTs. This approach encodes complex distributed protocols like Paxos or Raft directly as RDTs, where synchronization drives the protocol forward. Surprisingly, this allows for strong consistency using only the mechanisms of eventually consistent RDTs.

This bears the question: Do we need anything else? Can’t we rely solely on RDTs and RDT-based protocols, stacking layers of eventual and strong consistency as required? This talk presents ongoing research into this programming model. We will discuss the potential building blocks of an RDT-only architecture, the role of composition, and strategies for verifying the correctness and consistency of such applications.