fp-ts-react

Functional Programming in React

Practical patterns for React apps. No jargon, just code that works.

Detailed Guide

Read [the detailed guide](references/detailed-guide.md) before executing this skill. It retains the complete procedure and reference material. Treat its safety, prerequisites, and validation requirements as mandatory. For focused work, load the relevant sections; for end-to-end work, read the guide completely.

When to Use This Skill

• When building React apps with fp-ts for type-safe state management
• When handling loading/error/success states in data fetching
• When implementing form validation with error accumulation
• When using React 18/19 or Next.js 14/15 with functional patterns

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When to Use What

| Situation | Use |

|-----------|-----|

| Value might not exist | Option<T> |

| Operation might fail (sync) | Either<E, A> |

| Async operation might fail | TaskEither<E, A> |

| Need loading/error/success UI | RemoteData<E, A> |

| Form with multiple validations | Either with validation applicative |

| Dependency injection | Context + ReaderTaskEither |

| Prevent re-renders with fp-ts | useMemo or fp-ts-react-stable-hooks |

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Limitations

• Use this skill only when the task clearly matches the scope described above.
• Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
• Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.