effect-v4

name	effect-v4
description	Effect v4 beta workflow for this repo. Use when writing, reviewing, migrating, or debugging Effect code, configuring Effect tooling, or deciding how agents should use the vendored Effect source.
metadata	{"internal":true}

Effect v4

This is an internal project-maintenance skill. It is not published as an installable skill from this repository.

Use Bun and the project-local Effect source. Do not use a global Effect clone.

Workflow

1. Read AGENTS.md and repos/effect/LLMS.md before writing Effect code. Completion criterion: the relevant Effect v4 pattern is grounded in the vendored source or its ai-docs.

2. Confirm package/source alignment. Completion criterion: package.json still pins effect@4.0.0-beta.94, and repos/effect remains read-only reference material from subtree split bdca35449d5dfce5b4433da75ec0a88d0a9b2b27.

3. Implement with Effect-native boundaries. Completion criterion: async SDK or platform calls enter through Effect.tryPromise; recoverable failures are typed errors; CLI entrypoints run one Effect program at the process boundary.

4. Keep the subtree out of app tooling. Completion criterion: tsconfig.json excludes repos, and Bun test scripts target project tests explicitly rather than recursive discovery.

5. Verify with Bun. Completion criterion: bun run typecheck and bun run test pass, or failures are explained with the exact command and relevant output.

Patterns

• Prefer Effect.gen for command workflows and Effect.fn("name") for reusable functions returning effects.
• Prefer services or gateway interfaces at external boundaries so tests can replace live SDK calls.
• Prefer Effect APIs over ambient globals when practical: Config over raw env in larger modules, Effect logging over ad hoc logs, Schema over untyped parsing at data boundaries.
• Keep v4 unstable imports behind narrow modules when they are needed; beta and effect/unstable/* APIs can change.

Bun

• Add dependencies with bun add.
• Add dev dependencies with bun add -d.
• For beta packages, pin exact versions unless the user explicitly asks to float.