Authoritative multiplayer game protocol
TabletopRPC.
One server-owned protocol for building trustworthy online tabletop games.
Case study
Focused software, built around a clear promise.
TabletopRPC is a game-agnostic Kotlin and Spring Boot service for online tabletop games. Clients submit commands instead of editing state locally; the server validates each move, advances authoritative state, and returns an ordered event stream. Six playable reference clients—from Tic-Tac-Toe and Blackjack to Checkers and heads-up Hold’em—prove the same protocol across very different rulesets.
The server decides
Clients send commands while the service validates rules, rejects stale versions, and remains the single authority for game state.
Retries stay safe
Optimistic concurrency and idempotency protect games from duplicate commands and unreliable network timing.
One protocol, many games
Reusable boards, cards, dice, pieces, turns, and ordered events support six playable demos without collapsing their distinct rules.