---
id: implementation/core-crate-deps
name: "Core: crate dependencies + module skeleton (alkcall wiring)"
status: completed
depends_on: []
scope: narrow
risk: low
impact: project
level: implementation
---

## Description

Add the dependency surface the wrapper layers need and the module
skeleton so the batch-1 core tasks have their targets. This is the
batch-1 analogue of the vendor scaffolding task: the crate gains
`alkcall` (its substrate, and first consumption of the 0.8.0 surface) and
the module files named in overview.md §Module Map, born wasm-clean.

Deliverables:

1. **`Cargo.toml` `[dependencies]`**: add to the existing trio
   (tokio wasm-clean subset, tracing, thiserror):
   - `alkcall = "0.8.0"` (pinned per AGENTS.md convention 11; bump
     deliberately, never transitively)
   - `serde = { version = "1", features = ["derive"] }`,
     `serde_json = "1"` (the params schema + spec builder)
   - `bytes = "1"` (the wire codec's buffer types)
   - `futures = { version = "0.3", default-features = false,
     features = ["std"] }` (BoxFuture for the seam callbacks, the
     alktunnels precedent; verify the wasm-clean subset compiles)
   - tokio stays `default-features = false` with the wasm-clean
     subset (`rt`, `sync`, `io-util`, `macros`, `time`); **never
     `features = ["full"]`** (AGENTS.md convention 4). No
     `tokio/net`, no `socket2`: those ride `local` in batch 2.
   - `[features]` stays `default = []`, `local = []`,
     `composed = []`, declared empty by design (ADR-009); populated
     by their modules' batch-2 tasks.
2. **`src/lib.rs`**: keep `#![forbid(unsafe_code)]` and the crate
   docs; declare the module skeleton per overview.md §Module Map:
   `params`, `wire`, `producer`, `consumer`, `egress`, `error`;
   one-line stub files, each with a module doc naming its filling
   task (the vendor-scaffolding precedent). `rfc1928` stays as is.
3. **Re-export posture**: `lib.rs` re-exports public API per
   convention 15; for now the module declarations only, and each
   implementation task adds its own re-exports.

## Acceptance Criteria

- [x] `cargo test` passes
- [x] `cargo clippy --all-targets -- -D warnings` clean
- [x] `cargo fmt --check` clean
- [x] `cargo check --target wasm32-unknown-unknown` clean; the wasm
      gate stays green with alkcall + serde + bytes + futures in the
      graph (alkcall 0.8.0's default crate is wasm-clean; verify, do
      not assume)
- [x] `cargo clippy --target wasm32-unknown-unknown -- -D warnings`
      clean
- [x] No `tokio/net`, `socket2`, `mio` in the default dependency
      graph (`cargo tree` spot-check)
- [x] `alkcall` pinned at `"0.8.0"` (not a range)
- [x] Module skeleton matches overview.md §Module Map (module names
      and file layout)

## References

- docs/architecture/overview.md §Dependencies, §Module Map
- docs/architecture/decisions/009-feature-gates.md (the feature
  layout; no `net` feature)
- AGENTS.md conventions 4 (tokio subset), 11 (alkcall pin), 15
  (module structure)
- Sibling posture: `/workspace/@alkdev/alktunnels/Cargo.toml`
  (alkcall 0.8.0 consumer; the futures/bytes/serde dep set)

## Notes

- Verified before implementing that alkcall 0.8.0 (the crates.io
  artifact, same resolution alktunnels uses) is wasm-clean with no
  `[patch]`/RUSTFLAGS need: its `getrandom 0.4 + wasm_js` is
  self-contained on `wasm32-unknown-unknown`. The `futures = {
  default-features = false, features = ["std"] }` subset compiles in
  the same graph (probe build in `/tmp/opencode/wasm-probe`).
- **Cargo.toml**: added `alkcall = "0.8.0"` (pinned, not a range, per
  convention 11), `serde = { version = "1", features = ["derive"] }`,
  `serde_json = "1"`, `bytes = "1"`, and
  `futures = { version = "0.3", default-features = false, features =
  ["std"] }` (the BoxFuture seam shape; the std-only subset, not
  default features. The latter is the same set in practice, but the
  explicit subset is the documented posture). tokio unchanged (the
  wasm-clean subset, `default-features = false`; never `full`); the
  full-tokio dev-dep stays native-only. `[features]` untouched
  (`default = []`, `local = []`, `composed = []`; ADR-009, populated
  by batch-2).
- **lib.rs**: kept `#![forbid(unsafe_code)]` + crate docs; declared
  the six skeleton modules per overview.md §Module Map: `params`,
  `wire`, `producer`, `consumer`, `egress`, `error` (alphabetical
  declaration order after `rfc1928`; rustfmt-sorted). No re-exports
  yet (convention 15 posture: each implementation task adds its own).
- **Stub files**: one-line module docs (2–5 lines) each naming its
  filling task: `params`/`error` → core-params-errors, `wire` →
  core-wire-codec, `egress` → core-seam-types, `producer` →
  core-producer-connect (+ associates/bind), `consumer` →
  core-consumer-connect (+ associates/bind). `door.rs`, `local/`,
  `composed/` are deliberately absent, being feature-gated batch-2 modules
  born with their features, per the overview module map's local/
  composed posture.
- Dep-graph spot checks: `cargo tree --target
  wasm32-unknown-unknown -e normal -i mio` and `-i socket2` print
  nothing (not in the wasm normal graph); the normal-only tokio
  feature set on both native and wasm targets is exactly
  `bytes/default io-util macros rt sync time` (the `net`/`full`
  features appear only via the dev-dependency tokio, which is the test-only
  surface, by design).

## Summary

Added the batch-1 dependency surface and the module skeleton:
`Cargo.toml` gains `alkcall = "0.8.0"` (the substrate pin,
convention 11), `serde`/`serde_json`, `bytes`, and the std-only
`futures` subset, with tokio's wasm-clean subset and the empty
`local`/`composed` features unchanged; `src/lib.rs` declares the six
skeleton modules (`params`, `wire`, `producer`, `consumer`, `egress`,
`error`) per overview.md §Module Map, each a stub with a module doc
naming its filling task (the vendor-scaffolding precedent); no
re-exports yet. Wasm-cleanliness verified before and after: alkcall
0.8.0's crates.io artifact compiles clean on
`wasm32-unknown-unknown` with no patching (probe build), and the
crate's checks all pass: `cargo test` (39+37 tests, 2 doc-ignored),
`cargo clippy --all-targets -- -D warnings`, `cargo fmt --check`,
`cargo doc --no-deps`, both wasm checks, and the `mio`/`socket2`/
`tokio::net` absence spot-checks on the default (normal) dependency
graph.