feat(ipc-codegen): add standalone codegen package + wire-compat examples

Makefile

@@ -55,7 +55,7 @@ endef
 
 # Fast bootstrap.
 fast: release-image barretenberg boxes playground docs aztec-up \
-		  bb-tests l1-contracts-tests yarn-project-tests boxes-tests playground-tests aztec-up-tests docs-tests noir-protocol-circuits-tests release-image-tests spartan claude-tests
+		  bb-tests l1-contracts-tests yarn-project-tests boxes-tests playground-tests aztec-up-tests docs-tests noir-protocol-circuits-tests release-image-tests spartan claude-tests ipc-codegen-tests
 
 # Full bootstrap.
 full: fast bb-full-tests bb-cpp-full yarn-project-benches
@@ -269,6 +269,17 @@ bb-tests: bb-cpp-native-tests bb-acir-tests bb-ts-tests bb-sol-tests bb-bbup-tes
 
 bb-full-tests: bb-cpp-wasm-threads-tests bb-cpp-asan-tests bb-cpp-smt-tests
 
+#==============================================================================
+# IPC Codegen
+#==============================================================================
+
+.PHONY: ipc-codegen ipc-codegen-tests
+ipc-codegen:
+	$(call build,$@,ipc-codegen)
+
+ipc-codegen-tests: ipc-codegen
+	$(call test,$@,ipc-codegen)
+
 #==============================================================================
 # .claude tooling
 #==============================================================================

barretenberg/.gitignore

@@ -9,7 +9,8 @@ cmake-build-debug
 *_opt.pil
 bench-out
 
-# Generated code from msgpack schema (run `yarn generate` in ts/)
+# Generated code (produced by ipc-codegen, not committed)
+**/generated/
+# Legacy generated paths from the cbind pipeline (kept for any leftover from migration)
 rust/barretenberg-rs/src/generated_types.rs
 rust/barretenberg-rs/src/api.rs
-ts/src/cbind/generated/

ipc-codegen/.gitignore

@@ -0,0 +1,11 @@
+# Local build artifacts produced by the echo wire-compat examples.
+examples/cpp/*/echo_client
+examples/cpp/*/echo_server
+examples/rust/*/target/
+examples/zig/*/.zig-cache/
+examples/zig/*/zig-out/
+examples/ts/*/node_modules/
+
+# All files under any generated/ directory are produced by bootstrap.sh build
+# (either codegen output or one-time-copied templates) and are never committed.
+**/generated/

ipc-codegen/.rebuild_patterns

@@ -0,0 +1,5 @@
+^ipc-codegen/src/.*\.ts$
+^ipc-codegen/templates/
+^ipc-codegen/examples/
+^ipc-codegen/package\.json$
+^ipc-codegen/bootstrap\.sh$

ipc-codegen/README.md

@@ -0,0 +1,166 @@
+# ipc-codegen
+
+Schema-driven IPC code generator for **C++**, **TypeScript**, **Rust**, and **Zig**.
+
+Given a JSON schema describing a service's commands and responses, emits matching
+type definitions plus a client and/or server in the target language. All wire I/O
+is msgpack-over-UDS; languages talk to each other byte-compatibly.
+
+## Quick start
+
+```sh
+cd ipc-codegen
+./bootstrap.sh build   # generate echo example bindings, compile all 4 languages
+./bootstrap.sh test    # run the 18-test cross-language wire-compat matrix
+```
+
+## Layout
+
+```
+ipc-codegen/
+  bootstrap.sh           # build / test / update_goldens / hash
+  src/                   # generator (TypeScript, runs under Node 22+)
+    generate.ts            # CLI entry point
+    schema_visitor.ts      # JSON schema -> CompiledSchema IR
+    cpp_codegen.ts         # IR -> C++ output
+    typescript_codegen.ts  # IR -> TypeScript output
+    rust_codegen.ts        # IR -> Rust output
+    zig_codegen.ts         # IR -> Zig output
+    naming.ts              # snake_case / PascalCase helpers
+  templates/             # static templates copied alongside generated code
+    cpp/{ipc_client,ipc_server,msgpack_struct_map_impl}.hpp
+    ts/{ipc_client,ipc_server}.ts
+    rust/{backend,error,ipc_client,ipc_server,uds_backend,ffi_backend}.rs
+    zig/{backend,uds_backend,ffi_backend,ipc_client,ipc_server,ffi_client}.zig
+  examples/              # 4-language echo service (test harness, see below)
+  SCHEMA_SPEC.md         # wire protocol and schema-format reference
+```
+
+The package contains no service schemas of its own. Each consumer owns and commits its schema next to the C++ server that defines the wire format, and invokes `generate.ts` with that local path.
+
+## CLI: `src/generate.ts`
+
+Invoked once per (schema, language) pair. Run directly with `node --experimental-strip-types`, or via `bootstrap.sh`.
+
+```
+node --experimental-strip-types --experimental-transform-types --no-warnings \
+  src/generate.ts --schema <file> --lang <ts|cpp|rust|zig> --out <dir> [flags]
+```
+
+### Required flags
+
+| Flag | Purpose |
+|---|---|
+| `--schema <file>` | Path to the JSON schema. |
+| `--lang <ts\|cpp\|rust\|zig>` | Target language. |
+| `--out <dir>` | Output directory. Files are (re)written every run; static templates are copied alongside (and re-copied only if missing for one-time scaffolding files). |
+
+### Role flags
+
+| Flag | Purpose |
+|---|---|
+| `--server` | Emit server dispatch (matches request name to handler, deserializes, calls handler, serializes response). |
+| `--client` | Emit a typed client class/struct with one method per command. |
+| `--uds` | Include the Unix-domain-socket backend (Rust/Zig). |
+| `--ffi` | Include the FFI backend (Rust/Zig). |
+
+### Naming flags
+
+| Flag | Purpose |
+|---|---|
+| `--prefix <Str>` | Type prefix applied to generated type names (`<Prefix>CircuitProve`, etc.). Auto-detected from the schema if omitted. |
+| `--strip-method-prefix` | TS only. Drops the prefix from client *method* names: `bbCircuitProve()` → `circuitProve()`. Types keep the prefix. |
+
+### C++-specific flags
+
+| Flag | Purpose |
+|---|---|
+| `--cpp-namespace <ns>` | C++ namespace, e.g. `bb::wsdb`. Default: lowercased prefix. |
+| `--cpp-wire-namespace <ns>` | Inner namespace for wire types, default `wire`. |
+| `--cpp-include-dir <path>` | Include-path prefix for cross-includes between generated files, e.g. `myservice/generated`. Leave unset when generated files are in the same directory as their consumer. |
+
+### Other
+
+| Flag | Purpose |
+|---|---|
+| `--curve-constants` | TS only. Also emit `curve_constants.ts` with bn254/grumpkin/secp moduli & generators (currently only used by bb). |
+| `--skeleton <dir>` | One-shot scaffolding: writes a `<service>_handlers.{ts,rs,zig,cpp}` stub, `main`, and a build file into `<dir>` if they don't already exist. Skipped on subsequent runs. |
+
+## Worked examples
+
+Paths below are illustrative — consumers commit their own schema next to the C++ server that owns the wire format and supply absolute or relative paths on the command line.
+
+### TypeScript client + server, with curve constants
+
+```sh
+src/generate.ts \
+  --schema /path/to/myservice_schema.json \
+  --lang ts \
+  --out /path/to/output/generated \
+  --server --client \
+  --prefix MyService --strip-method-prefix --curve-constants
+```
+
+Produces `api_types.ts`, `async.ts`, `sync.ts`, `server.ts`, `ipc_client.ts` (template), `ipc_server.ts` (template), `curve_constants.ts`.
+
+### C++ server + client, under a project sub-include path
+
+```sh
+src/generate.ts \
+  --schema /path/to/myservice_schema.json \
+  --lang cpp \
+  --out /path/to/myservice/generated \
+  --server --client \
+  --cpp-namespace my::ns --prefix MyService \
+  --cpp-include-dir myservice/generated
+```
+
+Produces `myservice_types.hpp`, `myservice_ipc_client.{hpp,cpp}`, `myservice_ipc_server.hpp`, plus the `ipc_client.hpp` / `ipc_server.hpp` / `msgpack_struct_map_impl.hpp` templates. Cross-includes use the supplied `--cpp-include-dir` prefix (`#include "myservice/generated/myservice_types.hpp"`).
+
+### Rust UDS + FFI client
+
+```sh
+src/generate.ts \
+  --schema /path/to/myservice_schema.json \
+  --lang rust \
+  --out /path/to/crate/src/generated \
+  --server --client --uds --ffi \
+  --prefix MyService \
+  --skeleton /path/to/crate/src
+```
+
+Produces `myservice_types.rs`, `myservice_client.rs`, `myservice_server.rs`, `ipc_server.rs` (template), plus the backend templates (`backend.rs`, `error.rs`, `uds_backend.rs`, `ffi_backend.rs`). The skeleton flag also writes a one-time `myservice_handlers.rs`, `main.rs`, and `Cargo.toml` into the skeleton dir so a new service crate is buildable on first run.
+
+### Zig client + server
+
+```sh
+src/generate.ts \
+  --schema /path/to/myservice_schema.json \
+  --lang zig \
+  --out /path/to/output/generated \
+  --server --client --uds --ffi \
+  --prefix MyService
+```
+
+Produces `myservice_types.zig`, `myservice_client.zig`, `myservice_server.zig`, plus backend templates.
+
+## Adding a new service
+
+1. **Define the C++ command structs** in your service's `.hpp`, each with `MSGPACK_SCHEMA_NAME` and `SERIALIZATION_FIELDS(...)`. Group them into a single `Command` and `Response` `NamedUnion`.
+2. **Snapshot the schema.** Build the service binary and run `<binary> msgpack schema` to dump the JSON. Commit it next to the C++ source that defines it (e.g. alongside the `Command` / `Response` headers). This is the wire-format source of truth.
+3. **Wire your consumer's build to invoke `src/generate.ts`** with the flags above, passing the absolute path to the committed schema and the desired output directory. Generated files go under a `generated/` directory which is gitignored by convention.
+4. **Run `./bootstrap.sh test`** in `ipc-codegen/` to confirm the codegen and cross-language wire compat tests still pass.
+
+## Schemas are the source of truth
+
+The JSON schema is the wire contract between client and server. Consumers commit it next to the C++ server that defines the underlying `SERIALIZATION_FIELDS`, so the file lives close to what it describes and tracks with that code. Whenever a server-side command changes, refresh the JSON snapshot by running `<binary> msgpack schema` against the rebuilt binary and committing the diff. Diverged schemas are a CI failure (each consumer is responsible for guarding its own snapshot).
+
+Each generated file embeds a `SCHEMA_HASH` so callers can detect at connection time that their bindings predate the server.
+
+## Wire-format contract
+
+`examples/echo-schema/golden/*.msgpack` is a frozen set of byte-level fixtures covering every relevant msgpack encoding boundary (variable-width ints, fixstr/str8/str16, bin8/bin16, optional `Some`/`None`, empty containers, multi-byte UTF-8). The per-language golden tests (`examples/{rust,ts}/echo/...`) both decode the fixtures and re-encode round-trip — pinning down canonical msgpack output across implementations.
+
+If you intentionally change the wire format, run `./bootstrap.sh update_goldens` and review the diff. Any byte-level change is a breaking change for external implementations of the schema.
+
+See `SCHEMA_SPEC.md` for the wire protocol details.