getify/Functional-Light-JS resource
Pragmatic, balanced FP in JavaScript. @FLJSBook on twitter. observed · 2026-08-28
Health v2 · maintenance only
32/100
- Activity 0
- Release rhythm 35
- Longevity 100
Flags: no_releases no_license
How is this computed?
round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10) — computed 2026-09-03. Adoption (stars, forks) is never an input.
- gap_med: n/a
- age_days: 3669
- days_rel: n/a
- days_push: 981
- n_releases_24m: 0
Adoption not part of the score
16738 stars · 1918 forks observed · 2026-08-28
What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded
Functional-Light JavaScript is a complete book by Kyle Simpson offering a pragmatic, balanced introduction to functional programming concepts applied to JavaScript. It is freely readable online and also sold in ebook formats, focusing on practical FP fundamentals without heavy mathematical terminology.
Use cases
- learn functional programming in javascript
- understand pure functions and immutability in js
- pragmatic fp without category theory jargon
- study closures currying and composition in javascript
- improve javascript code quality with fp principles
- free online book on functional javascript
When to choose
- you already know JavaScript and want to apply FP ideas pragmatically
- you prefer plain-language explanations over heavy FP terminology
- you want a free, complete, in-depth text on FP in JS
When to avoid
- you need a beginner-level intro to JavaScript itself
- you want a formal, mathematically rigorous treatment of FP
- you need a runnable library rather than learning material
Facets
learning-resource · maturity stable
developer-tools programming-languages tutorials education browser book functional-programming javascript free-online-book kyle-simpson nodejs
9 sources
- readme: https://github.com/getify/Functional-Light-JS · fetched 2026-08-28 · 8f86b4d07649
- homepage: http://FLJSBook.com · fetched 2026-08-29 · 7c4715f8987f
- site_page: https://leanpub.com/about · fetched 2026-08-29 · a3ffdd2e2a46
- registry_npm: https://registry.npmjs.org/functional-light-js · fetched 2026-08-29 · 0a3567da0138
- site_page: https://leanpub.com/authors · fetched 2026-08-29 · 8047e75e1d4b
- site_page: https://help.leanpub.com/reader-help/what-formats-do-leanpub-books-come-in · fetched 2026-08-29 · d570a1b8b3ed
- site_page: https://help.leanpub.com/en/articles/4405350-leanpub-author-faq · fetched 2026-08-29 · 6798dddde50d
- site_page: https://leanpub.com/help/api · fetched 2026-08-29 · a3f97ef691e5
- site_page: https://help.leanpub.com/en/articles/3788293-the-leanpub-faq · fetched 2026-08-29 · bab4d516dc40
Member repositories
| Repository | Role | Health v2 |
|---|---|---|
| getify/Functional-Light-JS | main | 32 |
For agents
markdown · JSON · MCP: product_card(name="getify/Functional-Light-JS")
Data as of 2026-08-30T08:39:29.467469+00:00 · Report a problem