retcomm-rbengine
Library · 2026
Platform-agnostic rollback engine whose snapshot ring underpins save states and rewind across the recomp ecosystems.
retcomm-rbengine describes itself as "A platform agnostic rollback engine for RetComM runtime environments". It is MIT-licensed, maintained by TechnicallyComputers, and was lifted from psxrecomp/runtime with the PSX-specific types removed so any recompilation host can use it.
What it provides
Modules for admit pacing, input history, hash confirm, and a tick-keyed snapshot ring.
Why it matters
The snapshot ring is the substrate that save states are built on, and the same machinery enables rewind: both were shown publicly in the PSXRecomp Tomba save states and rewind showcase video (2026-08-12). It also pairs with recomp-net, where rollback netcode support is developing.
The library ships no game data of any kind; it is infrastructure that recompilation projects link against.