Replay a run yourself.
This page loads a recorded run and re-derives every record in your
browser with machine.Step, the same function that committed
them on the Mac, compiled to WebAssembly. Each record must hash to the
stamp it is stored under and be exactly what the step derives from its
input. Then change one byte and watch the check fail.
Loading replay (about 3.7 MB)…
Edit either one: the run is replayed again as you type.
Integrity, not provenance.
Each record stores its predecessor's stamp and the hash of the exact bytes it observed, so the head hash commits to every record and every input before it. If replay reaches the head, nothing was changed, and every state was derived by this function from these observations.
That the observations came from a real model. A consistent chain can be built offline. These runs use a deterministic fake Codex app-server, and say so. Each head hash is published in the repository when its run is recorded, which shows the record existed then and was not edited later.
What runs here is controller/runtime/replay and
controller/core, built with GOOS=js GOARCH=wasm.
Nothing is checked on a server. The bundles are in
runs/; open one and read it.