hakorune/docs/private/roadmap/phases/phase-15.7/async-sync-lowering.md

Phase‑15.7 — Async/Sync Lowering Plan (Short)

Scope

• Stabilize callAsync → scheduler → FutureBox across backends.
• Keep LLVM path green via ny‑llvmc (crate) and llvmlite harness for minimal async.

Milestones

1. Docs first (this file; guides/async-model.md; llvm‑hako‑abi async notes) — done
2. Smokes
   • quick‑selfhost: callable_async, callable_async_parallel — green
   • curated_llvm: async‑await‑min — keep green; spawn -> SKIP until builder fix
3. Builder fixes (llvmlite)
   • Implement _resolve_arg in Python builder to support spawn/instance
   • Add timeouts for harness subprocess; Fail‑Fast on missing .o
4. Batch timer harness
   • Reduce TimerBox checks (batching+calibration) in fixed‑time suite
   • Optional async‑timer flag for stop‑flag scheduling
5. Parity sweep
   • Rust VM ↔ Hakorune‑VM ↔ LLVM ops/sec within target bands on fixed‑time suite

Policies

• Sync default; async opt‑in only. No silent fallbacks.
• Determinism mode denies external IO/threads (futures must be pure compute or error).