You keep saying deterministic… What are you actually trying to say?
Based on your docs: I mean googling “deterministic temporal.dev” brings up nothing. I found other libraries and I get it. I assume you mean, “replayable by our engine,” but that would give away: replayability of most code in all the languages you support is hopelessly out of scope. “Pure” isn’t even a useful constraint - lots of code looks pure, but basically none of Python is, because you will alloc by so much as sneezing and hence you can OOM. Why promise the world?
Determinism means that the control logic should lead to the same set of behaviours every time with the same set of inputs under otherwise normal runtime conditions.
And if you're gonna come back with "but that's not real determinism!" then I would remind you that actually no code is deterministic because of quantum uncertainty, and that quantum uncertainty isn't necessarily real because of solipsism, and that there's more to life than rhetorical definition interrogations.