Module model 

Concurrency memory model — the normative determinacy table.

See docs/CONCURRENCY_MODEL.md and work/FINISH_INTERPRETER.md §3 for the full specification. The short version:

• Determinate fragment = LaunchTask + FIFO Pipe/Send/Receive + data-independent Concurrent/Parallel + CRDT shared state. By Kahn’s determinacy theorem (Kahn Process Networks, 1974) the observable output of such a program is scheduling-independent.
• Nondeterminate fragment = the moment a program reaches a Select (Await the first of:), an After timeout branch, a Try to send/receive, or a Stop it can observe which event won a race — a function of timing, not of channel histories. Those four constructs are the determinacy frontier.

Structs

NondetWitness

A single nondeterminism source found in the program.

Enums

Determinacy

Whole-program determinacy verdict.

NondetKind

The constructs that force nondeterminism — the determinate↔nondeterminate frontier.