Tech Stack Detector — CMS, Frameworks & Analytics

Detect what any website is built with: CMS, frameworks, JavaScript libraries, analytics, web servers, CDN and hosting — from 7,500+ community-maintained fingerprints, with versions where detectable and the evidence for every match (which header, cookie, meta tag or script gave it away). One GET per URL, no crawling, no credentials.

What it does

Give it a list of website URLs (bare domains work — https:// is assumed). For each site you get one dataset item with:

• technologies[] — every detected technology:
  • name and categories (CMS, JavaScript libraries, Analytics, …)
  • version when the fingerprint can extract one (e.g. jQuery 3.6.0, WordPress 6.4)
  • evidence[] — exactly what matched: headers:server, cookies:phpsessid, meta:generator, scriptSrc, html, url, or implied by WordPress
• byCategory — {"CMS": ["WordPress"], "Web servers": ["Nginx"]} summary
• technologyCount, finalUrl, httpStatus, checkedAt

Implied technologies are expanded transitively (WordPress ⇒ PHP ⇒ MySQL). Failed pages (404, non-HTML, timeouts) produce a failed item with a clear error — batch jobs always finish.

Input

Field	Type	Default	Description
urls	array	—	Websites to analyze (only these are fetched; no crawling)
timeoutSecs	integer	20	Download timeout per page
maxFileSizeMb	integer	5	Larger pages are skipped with a failed item

Example output (abridged)

{
    "url": "https://github.blog",
    "status": "success",
    "technologies": [
        {"name": "Nginx", "categories": ["Web servers", "Reverse proxies"], "version": null, "evidence": ["headers:server"]},
        {"name": "WordPress", "categories": ["CMS", "Blogs"], "version": "7.0.4", "evidence": ["meta:generator", "html"]},
        {"name": "MySQL", "categories": ["Databases"], "version": null, "evidence": ["implied by WordPress"]},
        {"name": "Yoast SEO", "categories": ["SEO"], "version": "28.2", "evidence": ["html"]}
    ],
    "technologyCount": 13,
    "byCategory": {"CMS": ["WordPress"], "Databases": ["MySQL"], "Web servers": ["Nginx"]},
    "checkedAt": "2026-08-18T09:30:00Z"
}

Typical uses

• Sales/market research: segment prospect lists by CMS, e-commerce platform or analytics stack
• Competitive analysis: what are competitors built on, did they migrate
• Security/IT inventory: find sites still running outdated library versions
• Enrich domain datasets with technology columns

Fingerprint database: license & updates

• The detection rules are a compact compilation of enthec/webappanalyzer — the community-maintained continuation of the Wappalyzer technology database — used under its GPL-3.0 license. The compiled snapshot (src/data/fingerprints.json) keeps the license notice plus provenance metadata (source repo, upstream commit hash, retrieval date) in its _meta block, and remains under GPL-3.0. The detection engine reads it as data.
• Updating: run python scripts/update_fingerprints.py (fetches the latest upstream DB, recompiles the snapshot, prints the new commit hash), then rebuild the Actor. We refresh the snapshot periodically.

Limitations

• Static analysis of the served HTML: technologies only visible after client-side JavaScript execution may be missed (js/dom fingerprints are out of scope by design)
• Sites behind aggressive bot protection may fail or reveal only their CDN
• Version extraction depends on the site exposing it (headers, generator tags, asset paths) — version is null when it doesn't

Development (local)

cd actors/tech-stack-detector
uv venv --python 3.13 .venv && uv pip install -p .venv/bin/python -r requirements.txt

.venv/bin/python tests/run_local_test.py           # end-to-end test (apify run equivalent), exit 0 = ALL PASS
../../node_modules/.bin/apify run                  # real apify CLI local run (input: storage/key_value_stores/default/INPUT.json)

The test runs a mock WordPress-behind-Nginx site against the real bundled DB (headers/cookies/meta/scriptSrc/html matching, version extraction, implies expansion read from the DB itself); expected results live in tests/expected_output.json. Publishing → ../../docs/publishing.md.