# stackblitz/alien-signals

👾 The lightest signal library

Repository: https://github.com/stackblitz/alien-signals
Canonical: https://ross.abutalabs.com/products/alien-signals
Homepage: https://npmjs.com/package/alien-signals
Language: TypeScript
License: MIT
License Family: permissive
Last push: 2026-06-10T12:29:02+00:00

## Health v2 (maintenance only)
Score: 71/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 86, release rhythm 51, longevity 74
- inputs: {"age_days": 1048, "days_push": 84, "days_rel": 113, "gap_med": 241.0, "n_releases_24m": 3}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 3236, forks 120 (observed 2026-08-28T04:07:50.296765+00:00)

## What it is
alien-signals is an extremely lightweight TypeScript signal library implementing a push-pull based reactivity algorithm. Its core algorithm has been ported into Vue 3.6 and is used in Vue language tools for incremental AST parsing and virtual code generation.

## Use cases
- add fine-grained reactive state to a JavaScript app
- use signals without pulling in a full framework
- benchmark or study reactivity algorithms
- build a custom reactive UI framework
- incremental computation for language tooling

## When to choose
- you need minimal-bundle, high-performance signals in TypeScript
- you want a framework-agnostic reactivity primitive
- you're building tooling that benefits from incremental recomputation

## When to avoid
- you want a batteries-included state manager with devtools and middleware
- you need framework-specific integrations out of the box
- you prefer a mature ecosystem over a research-oriented library

## Facets
- artifact type: library
- maturity: active
- function: state-management, developer-tools
- domain: frontend, web-development, performance
- platform: browser, cross-platform
- tags: signals, reactivity, push-pull, fine-grained-reactivity, vue, nodejs, typescript

## Member repositories
- stackblitz/alien-signals (main) score 71

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:07:50.296765+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 2026-08-30T07:24:36.103568+00:00, confidence not recorded.
  - readme: https://github.com/stackblitz/alien-signals (fetched 2026-08-28T04:07:50.296765+00:00, sha 41ad849413dd)
  - registry_npm: https://registry.npmjs.org/alien-signals (fetched 2026-08-29T09:37:38.400423+00:00, sha b7ce3005c609)
- Data as of 2026-08-30T08:39:29.467469+00:00.