Give the Rust CultMesh runtime a home

The only Rust CultMesh implementation in existence was 1,363 lines inside
Ghostlight's vendor directory. It was in no library repo and no standalone
repo, so it had never been checked against the browser, Kotlin, and
TypeScript CultMesh bodies it must interoperate with.

It is not a duplicate of the facade in cultnet-rs. That one is the small
surface the parity table claims for Rust: peer cards, authority leases,
endpoint parsing. This is the stream and session layer -- node, document
sets, RUDP document publication, stream descriptors, negotiation, stream
catalog, and shared-memory frame rings -- which the same table lists under
Rust's "Not claimed". A consumer grew the unclaimed surface because there was
nowhere else to put it.

Its path dependencies already matched this layout and it builds against
CultLib's cultnet-rs unchanged, so it does not depend on the forked RUDP
extras. Seven runtime-local tests pass, and CI now runs them.

The parity table gains no claim from this. The Rust row says plainly that no
interop lane exercises the stream surface, and expansion work records that
runtime-local tests are not a parity claim. Landing code is not evidence.

packages/cultmesh-rs needed an explicit .gitignore re-include; the NuGet
packages rule hides every language package until one is added by name.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

.github/workflows/cultnet-interop.yml

@@ -92,6 +92,9 @@ jobs:
       - name: Verify Rust RUDP reliability
         run: cargo test --manifest-path packages/cultnet-rs/Cargo.toml rudp
 
+      - name: Verify Rust CultMesh runtime-local surface
+        run: cargo test --manifest-path packages/cultmesh-rs/Cargo.toml
+
       - name: Verify C# RUDP reliability
         run: dotnet test tests/GameCult.Networking.Tests/GameCult.Networking.Tests.csproj --filter "FullyQualifiedName~Rudp"
 

.gitignore

@@ -307,6 +307,8 @@ node_modules/
 !packages/cultcache-rs/**
 !packages/cultnet-rs/
 !packages/cultnet-rs/**
+!packages/cultmesh-rs/
+!packages/cultmesh-rs/**
 packages/**/node_modules/
 packages/**/dist/
 packages/**/dist-test/

docs/runtime-parity-scope.md

@@ -33,7 +33,7 @@ CultMesh.
 | C# | Reference implementation and production game/server substrate | CultCache typed documents and SoA, CultNet schema-v0, LiteNetLib production path with adapter profile, shared transport profiles, shared RUDP socket transport, C# multi-peer RUDP listener and schema service host, C# interop RUDP serve/dial path, connected RUDP CultMesh client helpers, RUDP-backed schema-client selection for `rudp://` service endpoints, RUDP reconnect policy/controller and reconnect-loop helper, LiteNetLib client reconnect-controller adoption, schema-client transport port for service request/response clients, CultMesh node/session/catalog/stream/simulation/RUDP surfaces, authorized peer lookup | No need to abandon LiteNetLib before the CultNet adapter fully owns production service adoption |
 | Python | Package runtime, local daemon endpoint, raw interop peer, typed state participant | CultCache/CultNet/CultMesh package surface, branded CultMesh node/schema/shard/Verse/peer/authority/stream/RUDP ergonomics, authorized peer lookup, shard catalogs/logs, schema-transport factory for raw client request/subscription flows, local TCP and RUDP CultMesh server listeners, Python interop RUDP serve/dial path, session/prediction/simulation fact helpers, RUDP codec/session/socket transport, RUDP reconnect policy/controller and reconnect-loop helper, schema-v0 MessagePack over RUDP evidence, benchmark evidence against C# cache paths | Universal C# throughput, full C# daemon/server stack, and RUDP as the only public service pipe |
 | TypeScript | Node/browser-adjacent projection and interop runtime | CultCache parity tests, CultNet schema-v0 peer, advertised schema/shard catalog wire contracts plus request/sync helpers, transport profiles, TCP-framed transport port and peer helper, shared RUDP socket transport, RUDP interop serve/dial path, RUDP reconnect policy/controller, RUDP reconnect-loop helper, branded CultMesh node/schema/shard/Verse/peer/authority/stream/RUDP ergonomics, authorized peer lookup | Full C# game session/server stack |
-| Rust | Low-level cache/transport/runtime substrate | CultCache/CultNet interop lane, schema and shard catalog helpers, typed same-schema alias hydration from raw snapshots, transport profiles, TCP-framed port, shared RUDP codec/session/socket transport, Rust interop RUDP serve/dial path, connected RUDP CultMesh client helpers, RUDP reconnect policy/controller and reconnect-loop helper, schema-v0 MessagePack over RUDP evidence, small CultMesh facade for schema registry, shard catalog, peer cards, authority leases, authorized peer lookup, RUDP endpoint parsing, and peer-card/authorized-peer RUDP client construction | Full CultMesh game-session/server facade, stream catalog, or production game-session server |
+| Rust | Low-level cache/transport/runtime substrate | CultCache/CultNet interop lane, schema and shard catalog helpers, typed same-schema alias hydration from raw snapshots, transport profiles, TCP-framed port, shared RUDP codec/session/socket transport, Rust interop RUDP serve/dial path, connected RUDP CultMesh client helpers, RUDP reconnect policy/controller and reconnect-loop helper, schema-v0 MessagePack over RUDP evidence, small CultMesh facade for schema registry, shard catalog, peer cards, authority leases, authorized peer lookup, RUDP endpoint parsing, and peer-card/authorized-peer RUDP client construction | Full CultMesh game-session/server facade or production game-session server. `packages/cultmesh-rs` now holds a Rust stream and session surface -- node, document sets, RUDP document publication, stream descriptors, negotiation, stream catalog, and shared-memory frame rings -- but no interop lane exercises it, so it carries no cross-runtime parity claim |
 | Kotlin | JVM/Android client substrate | Typed MessagePack cache, one-call typed snapshot document sync through local same-schema aliases, built-in schema catalog advertisement, schema/shard catalogs with shared schema-message transport fetch/sync helpers, authority leases, authorized peer lookup, stream catalog, branded `CultMesh` facade, WebSocket transport profile/connection helper, RUDP client/server sugar, connected RUDP CultMesh client helpers, Kotlin interop RUDP serve/dial path, RUDP reconnect policy/controller and reconnect-loop helper, schema-v0 MessagePack over RUDP evidence | C# SoA store, full C# server daemon, or Unity hot-loop memory layout |
 
 ## Evidence Gates
@@ -85,6 +85,10 @@ server body, is deliberately not made.
   backfilling C# server responsibilities it should not own. Kotlin WebSocket
   and RUDP adapters now share one `CultNetSchemaMessageTransport` helper shape
   for schema/shard catalog request and sync flows.
+- Bring `packages/cultmesh-rs` under the wire claim. It arrived from a consumer repo where it grew
+  outside any conformance harness, and its stream, negotiation, and shared-memory frame-ring
+  surfaces have never been checked against the browser, Kotlin, and TypeScript CultMesh bodies
+  they must interoperate with. Runtime-local tests pass; that is not a parity claim.
 - Keep performance claims evidence-bound: C# owns SoA; Python has benchmark
   comparison gates; other runtimes should advertise measured native hot paths
   only when those paths exist.

packages/cultmesh-rs/Cargo.toml

@@ -0,0 +1,20 @@
+[package]
+name = "cultmesh-rs"
+version = "0.1.0"
+edition = "2024"
+publish = false
+
+[lib]
+name = "cultmesh_rs"
+path = "src/lib.rs"
+
+[dependencies]
+anyhow = "1"
+cultcache-rs = { path = "../cultcache-rs" }
+cultnet-rs = { path = "../cultnet-rs" }
+serde = { version = "1", features = ["derive"] }
+
+[dev-dependencies]
+pretty_assertions = "1.4.1"
+rmp-serde = "1"
+tempfile = "3"