# GoogleChromeLabs/jsvu

JavaScript (engine) Version Updater

Repository: https://github.com/GoogleChromeLabs/jsvu
Canonical: https://ross.abutalabs.com/products/jsvu
Homepage: https://mths.be/jsvu
Language: JavaScript
License: Apache-2.0
License Family: permissive
Topics: javascript, javascript-engine, installer, installer-script
Last push: 2026-07-30T06:07:03+00:00

## Health v2 (maintenance only)
Score: 75/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 95, release rhythm 35, longevity 100
- inputs: {"age_days": 3199, "days_push": 34, "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 2029, forks 98 (observed 2026-08-28T04:06:07.096007+00:00)

## What it is
jsvu is a CLI tool from GoogleChromeLabs that installs and updates recent versions of multiple JavaScript engines (V8, SpiderMonkey, JavaScriptCore, Hermes, QuickJS-ng, GraalJS, XS) without compiling from source. It runs on macOS, Windows, and Linux and is managed via npm.

## Use cases
- install javascript engines without compiling from source
- keep v8 and spidermonkey binaries up to date
- test my code against multiple js engines
- download prebuilt javascriptcore for mac arm
- manage multiple javascript engine versions on one machine
- get a quickjs or hermes binary quickly

## When to choose
- you need recent builds of several JS engines for testing or benchmarking
- you want prebuilt binaries instead of building engines from source
- you work on cross-platform JS engine compatibility

## When to avoid
- you only need Node.js itself (use nvm/fnm instead)
- you need a specific older engine version or custom build flags
- your platform/architecture is not in the supported matrix

## Facets
- artifact type: cli-tool
- maturity: active
- function: cli, package-manager, developer-tools, deployment
- domain: developer-tools, programming-languages
- platform: cli, windows, cross-platform
- tags: javascript-engines, version-manager, v8, spidermonkey, javascriptcore, hermes, quickjs, graaljs, prebuilt-binaries, command-line, javascript, nodejs, macos, linux

## Member repositories
- GoogleChromeLabs/jsvu (main) score 75

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:06:07.096007+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 2026-08-30T02:59:36.722150+00:00, confidence not recorded.
  - readme: https://github.com/GoogleChromeLabs/jsvu (fetched 2026-08-28T04:06:07.096007+00:00, sha 6a934a4b59e4)
  - homepage: https://mths.be/jsvu (fetched 2026-08-29T10:39:43.887623+00:00, sha 852f8118c682)
  - registry_npm: https://registry.npmjs.org/jsvu (fetched 2026-08-29T10:39:43.890255+00:00, sha 848986d9c9bf)
- Data as of 2026-08-30T08:39:29.467469+00:00.