Ash Framework

Canonical FP bar: docs/fcis-engineering-rules.md — Functional Core, Imperative Shell: pure domain modules; side effects at edges. Prefer Ash actions as explicit boundaries; avoid ad-hoc side effects inside pure computations.

RULES — Follow these with no exceptions

1. Use use Ash.Resource for domain resources — never manually implement protocols 2. Define actions explicitly — don't rely on defaults [:read, :create] without understanding what they expose 3. Add policies for authorization — every resource with sensitive data must have explicit policy blocks 4. Use Ash.Changeset.for_create/3 and Ash.Changeset.for_update/3 — not bare struct manipulation 5. Run mix ash_postgres.generate_migrations before manual migration — let Ash generate the schema 6. Verify resource loads — run mix compile and confirm no Spark.Error.DslError before proceeding

End-to-End Workflow

Follow this sequence when starting a new Ash project: