Genericity Matrix

Summary

This page states precisely what is reusable as-is, what is a template to adapt, and what is app-specific and must be authored. Use it to scope a new build.

Reusable as-is (do not rewrite)

Area	Artifact
Layering & dependency rule	the package layout and import rules
Composition root	the `init.py` shape, idempotency, `get_svc` overloading
Web edge	`OpenAPIFirstApp` bootstrap, handler-name = `operationId`, thin handlers
CRUD slice	the four-file pattern (model / ports-db / ports-service / converters)
Generic CRUD service	the base service adaptor
Repository factory	base / populating / cached selection
Worker	the poll loop, backoff, retry, status machine
Progress bus	the bus port + in-memory adapter + streaming endpoint
Human-in-the-loop	the durable pause + question document + resolve endpoint + resume map
Infra adaptors	HTTP cache decorator, KV store port, LLM pool scaffold
Testing	integration harness with fakes, fixture-parity pattern
Docs	GSDFC + generated stubs + MCP bundle pipeline

Template to adapt (copy, then change names)

Artifact	Change
`pyproject.toml`	project name, dependencies
`Dockerfile` / `docker-compose.yaml`	service name, ports, services
`.env.example`	connection strings, provider keys
`openapi.yaml`	every path/schema/operationId
`scripts/`	seed and operator tasks

App-specific (must be authored)

Artifact	Why
Resource models	the business shape
Repository populate/cache rules	the relationships
Service business logic	domain behaviour
Pipeline families (if any)	the transformation graph
Pattern/rule resources	data-driven policy
Fixtures & golden outputs	test data

The two axes

Everything app-specific reduces to two axes:

Resource model — the set of resources, their fields, relationships, and the OpenAPI contract.
Pipeline family — only if inputs require multi-step transformation.

If you can specify those two axes, the rest of the app follows mechanically.