Tech Stack Detection API — Brevo Delivery

Detect any website's marketing stack, ESP, CRM, analytics, and 100+ technologies using multiple detection methods: DNS records, HTML analysis, HTTP headers, and JavaScript runtime inspection.

Built by Gab @ Bulldozer

Features

• Multi-method detection — DNS (MX, SPF, CNAME), HTML parsing, HTTP headers, JS globals
• 100+ technologies across 12 categories
• 3 detection modes — full (browser + DNS), smart (DNS first, browser if needed), fast (DNS-only)
• Technographic scoring — 0-20 score based on detected ESP/marketing stack
• Clay/CSV integration — flat response format with format=clay
• Batch processing — up to 500 domains per request in fast mode
• In-memory caching — configurable TTL, avoids redundant lookups
• Docker-ready — Playwright + Chromium pre-installed

Quick Start

# Install dependencies
npm install
npx playwright install chromium

# Start the server
npm start

# Test a domain
curl "http://localhost:3000/api/techstack?domain=allbirds.com"

API Endpoints

GET /api/techstack

Detect tech stack for a single domain.

Parameter	Type	Default	Description
domain	string	required	Domain to analyze (e.g. allbirds.com)
mode	string	full	Detection mode: full, smart, or fast
format	string	—	Set to clay or flat for flat key-value response
refresh	string	—	Set to true to bypass cache

Full response:

{
  "domain": "allbirds.com",
  "duration_ms": 5200,
  "cached": false,
  "tech_score": 5,
  "tech_stack_primary": "Klaviyo",
  "tech_category": "Ecommerce Specialist",
  "esp": [
    { "name": "Iterable", "confidence": "high", "source": "cname" },
    { "name": "Klaviyo", "confidence": "high", "source": "js" }
  ],
  "ecommerce": [
    { "name": "Shopify", "confidence": "high", "source": "meta" }
  ],
  "analytics": [...],
  "marketing": [...],
  "chat": [...],
  "crm": [...],
  "cms": [...],
  "cdn": [...],
  "ab_testing": [...],
  "tag_manager": [...],
  "payment": [...],
  "hosting": [...],
  "dns_records": { "mx": [...], "txt": [...], "cname": [...] },
  "detection_methods": {
    "dns": true,
    "html": true,
    "headers": true,
    "javascript": true
  }
}

Flat response (format=clay):

{
  "domain": "allbirds.com",
  "esp": "Iterable, Klaviyo",
  "esp_count": 2,
  "ecommerce": "Shopify",
  "ecommerce_count": 1,
  "analytics": "Google Analytics, Hotjar",
  "analytics_count": 2,
  "klaviyo": "Klaviyo + Shopify",
  "tech_score": 5,
  "tech_stack_primary": "Klaviyo",
  "tech_category": "Ecommerce Specialist",
  "cached": false,
  "duration_ms": 5200
}

POST /api/techstack/batch

Detect tech stacks for multiple domains in parallel.

curl -X POST "http://localhost:3000/api/techstack/batch" \
  -H "Content-Type: application/json" \
  -d '{"domains": ["allbirds.com", "vuoriclothing.com"], "mode": "fast"}'

Mode	Max domains	Concurrency	Speed
fast	500	50	~500ms/domain
smart	200	20	~3-5s/domain avg
full	20	5	~15s/domain

POST /api/cache/clear

Clear all cached results. Requires API key if authentication is enabled.

GET /health

Health check (no auth required). Returns cache stats.

Detection Modes

Mode	How it works	Best for
full	DNS + browser in parallel (default)	Maximum accuracy
smart	DNS first → browser only if tech score >= 15	Balance of speed + accuracy
fast	DNS-only, no browser	Bulk processing, quick ESP lookup

Categories Detected

Category	Examples
ESP	Klaviyo, Mailchimp, SendGrid, HubSpot, ActiveCampaign, Iterable, Customer.io, Brevo, +35 more
CRM	Salesforce, HubSpot, Zoho, Pipedrive, Freshsales, Microsoft Dynamics, +15 more
Analytics	Google Analytics, Mixpanel, Amplitude, Heap, Segment, Hotjar, FullStory, +10 more
E-commerce	Shopify, BigCommerce, Magento, WooCommerce, Salesforce Commerce Cloud, +7 more
Marketing	Facebook Pixel, TikTok, Pinterest, LinkedIn, Google Ads, Criteo, +10 more
Chat	Intercom, Drift, Zendesk, Gorgias, Tidio, LiveChat, +15 more
A/B Testing	Optimizely, VWO, AB Tasty, Dynamic Yield, LaunchDarkly, +5 more
Tag Manager	GTM, Adobe Launch, Tealium, Segment, +3 more
CMS	WordPress, Next.js, Nuxt.js, Webflow, Drupal, Squarespace, +8 more
CDN	Cloudflare, Fastly, Akamai, CloudFront, Bunny CDN, +10 more
Payment	Stripe, PayPal, Klarna, Affirm, Adyen, +7 more
Hosting	AWS, Google Cloud, Azure, Heroku, Vercel, Netlify, +15 more

Technographic Scoring

Each detection returns a tech_score (0-20) based on the primary ESP detected:

Score	Category	Meaning
20	SMB Email & Marketing Automation	Mailchimp, ActiveCampaign, Campaign Monitor, etc.
15	Email API / SMTP	SendGrid, Mailgun, Postmark, Amazon SES
10	Legacy / Mid-market Platforms	Emarsys, Dotdigital, Listrak, Sailthru
5	CDP / Sophisticated Stack	Braze, Iterable, Customer.io, Segment
5	Leading CRM Suite	HubSpot
0	Enterprise Marketing Suites	Salesforce Marketing Cloud, Marketo

Special: Klaviyo scores 5 with Shopify (ecommerce specialist), 20 without (SMB email).

Authentication

Set the API_KEY environment variable to enable authentication. If not set, all endpoints are open.

# With auth enabled
curl -H "X-API-Key: your-key" "http://localhost:3000/api/techstack?domain=example.com"

# Or via query param
curl "http://localhost:3000/api/techstack?domain=example.com&api_key=your-key"

Docker

# Build
docker build -t techstack-api .

# Run
docker run -p 3000:3000 -e API_KEY=your-key techstack-api

Environment Variables

Variable	Default	Description
PORT	3000	Server port
API_KEY	—	API key for authentication (optional, auth disabled if not set)
CACHE_TTL_HOURS	24	Cache expiration in hours

Detection Methods

1. DNS Records — MX, TXT/SPF, CNAME lookups for ESP, CDN, hosting, and CRM detection
2. HTML Analysis — Script sources, meta tags, inline scripts, link hrefs
3. HTTP Headers — Server, X-Powered-By, X-CDN headers
4. JavaScript Globals — Runtime detection of 50+ known globals (Klaviyo, Shopify, GTM, etc.)

Architecture

src/
├── index.js              # Express API server, endpoints, routing
├── services/
│   ├── detector.js       # Multi-method detection engine (DNS + Playwright)
│   ├── scoring.js        # Technographic scoring (0-20 pts)
│   ├── cache.js          # In-memory TTL cache
│   └── flatten.js        # Clay/CSV flat format converter
├── middleware/
│   └── auth.js           # Optional API key authentication
└── data/
    └── signatures.js     # 100+ technology detection signatures

Performance Notes

• Browser recycled every 50 requests to prevent memory bloat
• DNS fallback when browser times out (partial results with partial: true)
• Smart mode skips browser for ~80% of domains → significant speed improvement
• In-memory cache avoids redundant lookups within TTL window

Testing

npm test

Runs detection against 10 real domains and reports ESP detection rates, coverage, and timing.

License

ISC