Phase 2: Multi-producer adoption

[hyperpolymath]

Tracking issue for Phase 2 of the production path. See docs/PRODUCTION-PATH.adoc §Phase 2.

Theme

Today AffineScript is the only realistic adopter (and only via Track B). For typed-wasm to be a real target, other compilers must target it. Phase 2 makes that possible and proves it works with ≥3 producers.

Deliverables

• Producer specification document — normative: what a third-party compiler must guarantee to emit valid typed-wasm. Today this lives implicitly in the verifier code; extract as external contract with examples and edge cases.
• C ABI for the verifier — wrap the Rust crate in a stable C API so Go/Python/C++/Java consumers can call it without binding to Rust
• Producer conformance test suite — corpus that any candidate compiler must satisfy. Analogue to the wasm reference test suite.
• "How to make your compiler target typed-wasm" cookbook — built from the AffineScript migration; the artifact other compiler authors actually consume
• ≥2 more reference producers beyond AffineScript — realistic candidates: Ephapax, TypedQLiser; plus one outside-ecosystem proof (academic language / MS thesis project)
• LLVM lowering guide — how LLVM IR concepts map to regions/levels. Not yet a backend; lets anyone with an LLVM frontend route through typed-wasm semi-mechanically.

Gate to Phase 3

1. ≥3 producers shipping wasm that passes the verifier
2. Producer specification has been stable for the last 2 adoptions (no breaking changes required)

Depends on

• Phase 1 complete — issue Phase 1: End-to-end producer #49

Status when this issue closes

typed-wasm enters the same category as wasm-bindgen (the standard "wasm + multi-language interop" surface) but with formal guarantees on top. At this point typed-wasm is "the standard way to opt into formal memory safety for any wasm producer." No direct peer at this maturity level.

Next phase

• Phase 3 — Runtime-side enforcement: issue Phase 3: Runtime-side enforcement #51

[hyperpolymath]

Unblocked — Phase 1's capstone gate is green ✅

#49 (Phase 1: End-to-end producer) is closed at its gate: #132 landed in #149 (squash 4d15643) and is verified executing on Wasmtime 45.0.0. There is now an in-tree .twasm → .wasm producer with verifier-backed soundness for linear memory, so Phase 2 (multi-producer adoption) can proceed.

Note: the Phase 1 breadth deliverables continue in parallel as standalone issues — #127 (remaining examples + parse → IR seam), #126, #129, #130, #140 — all gated on provisioning the AffineScript/OCaml toolchain in the environment. They don't block starting Phase 2 work, but #127's seam is the shared dependency to watch.

---

Generated by Claude Code