add-bounded-context

Imported from C3EQUALZz/agate (.claude/skills/add-bounded-context/SKILL.md). Install upstream with npx skills add C3EQUALZz/agate --skill add-bounded-context. Copyright stays with the author.

Add a bounded context (crate)

Each bounded context is its own crate under crates/. It owns its aggregates and domain. There is no shared kernel; if two contexts need the same technical capability, publish it as a generic-subdomain library crate (like agate-crypto), not a shared domain model.

Steps

1. Create the crate crates/agate-<context>/ with Cargo.toml:

   [package]
   name = "agate-<context>"
   version.workspace = true
   edition.workspace = true
   license.workspace = true
   description = "<one line>"
   
   [dependencies]
   # only inward deps: other domain/generic-subdomain crates. NO async runtimes,
   # NO hyper/axum/reqwest/extism in a crate that exposes a pure domain.
   
   [lints]
   workspace = true

   If other crates depend on it, register it in root [workspace.dependencies] with a version ({ path = "...", version = "0.1.0" }) to avoid a cargo-deny wildcard.

2. Lay out layers as modules inside the crate:

   src/lib.rs            # pub mod domain; (then application/infrastructure as they appear)
   src/domain/
     common/             # seedwork: entities/ values/ services/ factories/ errors/ events/
     <subdomain>/        # values/ entities/ services/ factories/ events.rs
   tests/                # integration / scenario tests
   

   common/ mirrors agate-audit's seedwork (base Entity, AggregateRoot, ValueObject, DomainService, Factory, DomainError, event machinery). Keep it per-crate — do not extract a cross-crate kernel.

3. Preserve the dependency rule. Dependencies flow inward only: presentation → infrastructure → application → domain. The crate graph is acyclic (Cargo enforces it); keep the domain modules free of async/I/O/framework imports.

4. Wire modules: every file is declared pub mod .. in its parent mod.rs and re-exported.

5. Verify with the check-architecture skill, then just ci.

See add-domain-object for populating the new context, and AGENTS.md for the conventions.