Revenant

You control one square with 20 seconds on the clock. Then the room resets and a ghost replays your last run, exactly. A door needs three buttons held at once but you have one body — so you team up with your past selves, loop after loop.

HIGHLIGHTS

• Custom fixed-point deterministic physics engine — replays are 100% repeatable
• 24 hand-built puzzle levels around cooperating with your own ghosts
• Rollback netcode and a Rust port of the simulation
• A proof suite that verifies the sim is bit-exact across runs and platforms

HOW IT’S BUILT

For a ghost to replay perfectly, the simulation has to be completely predictable — so the physics engine is written from scratch with fixed-point math (no floats, no drift), no game framework. That determinism unlocks the rest: 24 levels, rollback netcode, a Rust port of the sim, and an automated proof suite that verifies bit-exact repeatability.

STACK