# enricopolanski/functional-programming

Introduction to Functional Programming using TypeScript and fp-ts.

Repository: https://github.com/enricopolanski/functional-programming
Canonical: https://ross.abutalabs.com/products/enricopolanski-functional-programming
Language: TypeScript
License: NOASSERTION
License Family: other
Archived: true
Last push: 2025-03-11T22:12:55+00:00

## Health v2 (maintenance only)
Score: 10/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 10, release rhythm 35, longevity 100
- inputs: {"age_days": 2426, "days_push": 540, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases, archived, no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1293, forks 94 (observed 2026-08-28T04:04:16.191600+00:00)

## What it is
An open-source educational book introducing functional programming concepts using TypeScript and the fp-ts library. It covers referential transparency, semigroups, monoids, algebraic data types, category theory, functors, and applicative functors.

## Use cases
- learn functional programming in typescript
- understand monads and functors with examples
- learn fp-ts library concepts
- study category theory for programmers
- learn algebraic data types in typescript
- functional error handling with option and either

## When to choose
- you want a structured, in-depth introduction to functional programming in TypeScript
- you are learning fp-ts and need explanations of its typeclass abstractions
- you prefer learning through theory grounded in a real language

## When to avoid
- you need a quick reference or API documentation for fp-ts
- you work in a language other than TypeScript
- you want hands-on projects rather than conceptual teaching

## Facets
- artifact type: learning-resource
- maturity: active
- function: documentation, developer-tools
- domain: tutorials, programming-languages
- platform: cross-platform
- tags: functional-programming, typescript, fp-ts, category-theory, monads, algebraic-data-types, ebook, algorithms, nodejs

## Member repositories
- enricopolanski/functional-programming (main) score 10

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:16.191600+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T04:54:41.707876+00:00, confidence not recorded.
  - readme: https://github.com/enricopolanski/functional-programming (fetched 2026-08-28T04:04:16.191600+00:00, sha 7237f0489f03)
- Data as of 2026-08-30T08:39:29.467469+00:00.