This mod potentially causes desyncs on multiplayer because the variables like is_space_age_loaded are stored in Lua context. When a new player joins, they will have a value of false, on_init will never file, so their value might not match the values for earlier players.

Thanks, I'll check that.

Thanks for the report.

You were right — the issue was caused by using Lua’s standard random functions.
I’ve updated the mod to use Factorio’s deterministic random generator stored in persistent state, which should prevent multiplayer desyncs, including for late joiners.

Thanks for pointing this out.

That didn’t address my point.

Thanks for the follow-up — I think there might be a small misunderstanding.

This mod currently doesn’t have a variable like is_space_age_loaded (or anything similar).

If you’re seeing behavior like that, it might be coming from another mod or an older version.
That said, your main point about multiplayer determinism is valid, and I did fix an issue related to Lua’s standard RNG in the latest version.

If you’re still seeing desyncs, a desync log or repro steps would help a lot.

I see that the variable was removed in an earlier version.

Thanks for checking — hope you enjoy the mod!