# laurentj/slimerjs

A scriptable browser like PhantomJS, based on Firefox

Repository: https://github.com/laurentj/slimerjs
Canonical: https://ross.abutalabs.com/products/slimerjs
Homepage: http://slimerjs.org
Language: JavaScript
License: NOASSERTION
License Family: other
Topics: slimerjs, casperjs, firefox, javascript, phantomjs
Last push: 2023-03-09T01:45:51+00:00

## Health v2 (maintenance only)
Score: 23/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 5012, "days_push": 1274, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2998, forks 254 (observed 2026-08-28T04:07:37.303866+00:00)

## What it is
SlimerJS is a scriptable headless browser that provides the PhantomJS API on top of Gecko (Firefox) instead of WebKit, letting external JavaScript scripts open pages, click links, fill forms, monitor network traffic, and take screenshots. It is compatible with CasperJS 1.1 and pinned to Firefox 59, with development officially ended in 2021.

## Use cases
- run functional tests of a web app in a real Firefox/Gecko engine
- automate web pages: open pages, click links, fill forms from a script
- take screenshots of web pages programmatically
- monitor network requests while loading a page
- run existing PhantomJS or CasperJS scripts on the Gecko engine
- scrape content from web pages with a scriptable browser

## When to choose
- you have legacy PhantomJS or CasperJS scripts and need them to run on Gecko/Firefox rendering
- you need page automation or testing that matches Firefox 59 rendering exactly
- you want a PhantomJS-compatible API with extra features like file I/O and a built-in webserver module

## When to avoid
- you are starting a new project - use Playwright, Puppeteer, or Selenium instead
- you need a modern Firefox version (60+) or current web standards support
- you need maintained software with security updates - the project officially ended in 2021

## Facets
- artifact type: cli-tool
- maturity: abandoned
- function: e2e-testing, web-scraping, http-client, testing
- domain: web-development, testing, developer-tools
- platform: windows, cli
- tags: headless-browser, phantomjs-compatible, gecko, firefox, casperjs, page-automation, screen-capture, network-monitoring, xul, automation, linux, macos, javascript

## Member repositories
- laurentj/slimerjs (main) score 23

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:07:37.303866+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 2026-08-30T07:30:37.023898+00:00, confidence not recorded.
  - readme: https://github.com/laurentj/slimerjs (fetched 2026-08-28T04:07:37.303866+00:00, sha b32fda813293)
  - homepage: http://slimerjs.org (fetched 2026-08-29T09:46:33.403333+00:00, sha ba1ffc05ffc0)
  - site_page: https://slimerjs.org/features.html (fetched 2026-08-29T09:46:33.412500+00:00, sha 432dbda57dca)
  - site_page: https://docs.slimerjs.org (fetched 2026-08-29T09:46:33.414724+00:00, sha 3aa804159cbc)
  - site_page: https://slimerjs.org/about.html (fetched 2026-08-29T09:46:33.419995+00:00, sha 8035a2143702)
  - registry_npm: https://registry.npmjs.org/slimerjs (fetched 2026-08-29T09:46:33.422026+00:00, sha 4c1cf1b94574)
  - site_page: https://slimerjs.org/faq.html (fetched 2026-08-29T09:46:33.417271+00:00, sha 09c3e006f0c0)
- Data as of 2026-08-30T08:39:29.467469+00:00.