The plain-English version
The property of producing matching accepted simulation results from the same stated initial state and ordered inputs within defined conditions.
Why it matters
It supports focused desynchronization diagnostics and reproducible examples.
Let’s make it click
Two runs of a short input log match at each chosen checkpoint in the supported build.
Vibe Bro’s heads-up
A shared seed alone does not establish this property. Godot documents its random generator algorithm as an implementation detail, so cross-version equivalence needs separate evidence.
You might also hear
- deterministic replay
- replay desync
- reproducible simulation
The docs behind it
Research sources reviewed .
Editorial review · October 28, 2026
Qualified: The bounded replay definition and seed caveat are sound. RNG algorithm stability is not promised, and Godot physics can diverge even without a source-code change; the text does not claim otherwise.