Agent skill · software engineering · aiskillstore
fp-ts-pragmatic
A practical, jargon-free guide to fp-ts functional programming - the 80/20 approach that gets results without the academic overhead. Use when writing TypeScript with fp-ts library.
Why this skill is useful
Provides practical patterns and examples for using the fp-ts library in TypeScript, which the AI may not generate reliably on its own.
What it needs
About 9k tokens when loaded. Last updated 2026-08-07. 405 stars on the source repository.
What this skill does
Pragmatic Functional Programming Read this first. This guide cuts through the academic jargon and shows you what actually matters. No category theory. No abstract nonsense. Just patterns that make your code better. When to Use This Skill When starting with fp-ts and need practical guidance When writing TypeScript code that handles nullable values, errors, or async operations When you want cleaner, more maintainable functional code without the academic overhead When refactoring imperative code to functional style The Golden Rule If functional programming makes your code harder to read, don't use it. FP is a tool, not a religion. Use it when it helps. Skip it when it doesn't. --- The 80/20 of FP These five patterns give you most of the benefits. Master these before exploring anything else. 1. Pipe: Chain Operations Clearly Instead of nesting function calls or creating intermediate variables, chain operations in reading order. When to use pipe: 3+ transformations on the same data You find yourself naming throwaway variables Logic reads better top-to-bottom When to skip pipe: Just 1-2 operations (direct call is fine) The operations don't naturally chain 2. Option: Handle Missing Values Without null Checks Stop writing if (x !== null && x !== undefined) everywhere. Plain language translation: O.fromNullable(x) = "wrap this value, treating null/undefined as 'nothing'" O.flatMap(fn) = "if we have something, apply this function" O.getOrElse(() => default) = "unwrap, or use this default if nothing" 3. Either: Make Errors Explicit Stop throwing exceptions for expected failures. Return errors as values. Plain language translation: E.right(value) = "success with this value" E.left(error) = "failure with this error" E.isRight(x) = "did it succeed?" 4. Map: Transform Without Unpacking Transform values inside containers without extracting them first. 5. FlatMap: Chain Operations That Might Fail When each step might fail, chain them together. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills aiskillstore/fp-ts-pragmatic