Core

The core layer is what every Cephalon app pulls in. It is the smallest, most stable surface — pure contracts and the composition engine.

Packages

Package	Maturity	What it ships
Cephalon.Abstractions	M4	Pure interfaces and types modules build against — IModule, ModuleDescriptor, Capability, ICapabilityRegistry, app-model types, transport types, technology contributor contracts.
Cephalon.Engine	M3	The composition engine — module discovery, dependency ordering, manifest v2, capability registry, lifecycle execution, integrity verification, cell boundary & CDC capture catalogs.
Cephalon.Scaffolding	M3	Project / folder / package scaffolding that powers cephalon new. Apps consume this only at scaffold time.
Cephalon.ReferenceDocs	M2	Optional reference-doc tooling that turns XML comments into Markdown for the docs site. Build-time only.

Engine contract at a glance

The engine guarantees, in order:

1. Validate the module set (no duplicate descriptors, no conflicting capability providers).
2. Order modules deterministically based on DependsOn.
3. Register module services into the DI container.
4. Compose capabilities and language packs from base + project + package contributions.
5. Execute lifecycle hooks (OnRegister → OnStart; OnStop runs in reverse order).
6. Expose the runtime manifest, runtime catalogs, and health aggregation.

The full ordered contract lives in Reference → Architecture → Runtime contracts.

What AddCephalonAspNetCore() does

The AspNetCore host adapter wires the engine into ASP.NET Core’s WebApplicationBuilder. It:

• registers the engine builder as a singleton.
• registers IRuntimeManifest for DI consumers.
• maps /engine/manifest, /engine/runtime, /engine/snapshot HTTP routes.
• maps the REST behavior pipeline.
• wires OpenAPI + Scalar for documenting the behaviors.
• exposes app.MapCephalon() which finalises the route registrations.

See Hosts for the equivalent on Cephalon.Worker and other adapters.

Source-doc snapshots

• Cephalon.Abstractions
• Cephalon.Engine
• Cephalon.Scaffolding

Cross-references

• Concepts — the smallest mental model.
• Architecture — the layered view.
• Module authoring — how to build on top.
• Reference → API — the generated API reference for the current version.