I built a small service that lets you watch replays of all old games or play singleplayer against any past version of OpenFront – just paste a game ID or pick a historical version.
Check it out: OpenFront Tools
If somebody is interested about the technical side: It’s a FastAPI service that clones OpenFrontIO as a bare mirror, builds any historical commit on demand inside a hardened sandbox, and serves the resulting static bundle so users can watch replays by game ID or play singleplayer against arbitrary release tags.