effect-typescript

name	effect-typescript
description	Use when writing, reviewing, or refactoring Effect 4 TypeScript code: Effect.gen, typed errors, Context.Service, Layer, Schedule, polling, resource safety, and strict inference.

Effect TypeScript

Use this skill for non-trivial work involving effect in this repo.

Canonical References

• Effect docs: https://effect.website/docs
• Effect LLM docs: https://effect.website/llms-full.txt
• Effect source: https://github.com/Effect-TS/effect
• Alchemy source: https://github.com/alchemy-run/alchemy-effect

Fetch docs before making claims about APIs that changed across Effect 4 betas.

Repo Constraints

• This repo currently tests alchemy@2.0.0-beta.59 with effect@4.0.0-beta.84.
• Do not bump to Effect beta.78 until a newer Alchemy beta containing upstream PR #542 is published.
• Keep provider implementation code inside Alchemy v2 lifecycle methods.
• Do not call Effect.runPromise in library/provider internals.
• Prefer typed tagged errors for recoverable cloud/API failures.

Patterns

• Use Effect.gen for sequential provider lifecycle logic.
• Use Effect.tryPromise({ try, catch }) at async boundaries.
• Use Effect.catchIf(isNotFound, ...) for idempotent delete/read recovery.
• Use Context.Service and Layer for credentials/services.
• Keep secret values in Redacted until SDK/API boundaries.

Review Checklist

• Are A, E, and R meaningful and not accidentally widened?
• Are errors recoverable by tag/predicate?
• Is polling bounded and failure explicit?
• Are resources deleted idempotently?
• Are TypeScript assertions hiding an inference/design problem?