# paldepind/flyd

The minimalistic but powerful, modular, functional reactive programming library in JavaScript.

Repository: https://github.com/paldepind/flyd
Canonical: https://ross.abutalabs.com/products/flyd
Language: JavaScript
License: MIT
License Family: permissive
Last push: 2024-02-05T20:10:57+00:00

## Health v2 (maintenance only)
Score: 32/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 4207, "days_push": 940, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1565, forks 82 (observed 2026-08-28T04:05:04.258348+00:00)

## What it is
Flyd is a minimalistic, modular functional reactive programming library for JavaScript built around composable observable streams. Its core is under 200 SLOC and exposes curried, functional-style operators with support for transducers and the Fantasy Land monad specification.

## Use cases
- manage values that change over time reactively in JavaScript
- combine event streams from clicks or inputs without heavy frameworks
- build custom reactive abstractions on a tiny stream core
- use transducers with Ramda to transform streams
- replace RxJS with a smaller, more functional FRP library

## When to choose
- you want a tiny, transparent FRP core you can fully understand
- you prefer curried functional operators over method chaining
- you need modular extensibility and atomic updates
- bundle size and simplicity matter more than ecosystem size

## When to avoid
- you need a large ecosystem of operators and community support like RxJS
- you want built-in scheduling, backpressure, or concurrency primitives
- you need TypeScript-first tooling or active ongoing development
- you are building modern apps where signals or RxJS are already available

## Facets
- artifact type: library
- maturity: maintenance
- function: state-management
- domain: web-development, frontend, developer-tools
- platform: browser, cross-platform
- tags: frp, reactive-programming, streams, functional-programming, observables, nodejs

## Member repositories
- paldepind/flyd (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:05:04.258348+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 2026-08-30T04:00:11.707751+00:00, confidence not recorded.
  - readme: https://github.com/paldepind/flyd (fetched 2026-08-28T04:05:04.258348+00:00, sha 41b369f8eeee)
  - registry_npm: https://registry.npmjs.org/flyd (fetched 2026-08-29T11:28:57.005093+00:00, sha eb6ed6cd533b)
- Data as of 2026-08-30T08:39:29.467469+00:00.