Pragmatic Effect

Use this as a simplification lens alongside the other Effect skills. Pragmatic Effect code is not "avoid Effect"; it is "use Effect where it buys typed effects, dependency boundaries, lifecycle, resource safety, retries, concurrency, or schemas; keep everything else plain."

Source check

Before implementing Effect-heavy code:

1. Inspect nearby code in the target repo.
2. Read project rules such as AGENTS.md, CLAUDE.md, package rules, or local Effect skills when present.
3. Prefer current Effect v4/effect-smol APIs and checked-in examples over old Effect v2/v3 memory. Call the Skill tool with "effect-v4" for the API reference and migration notes.
4. If a source file referenced by instructions is missing, say so and continue with available local examples.

Simplification rule

Ask these before adding machinery: