A comprehensive subdomain enumeration tool that combines Subfinder and Sublist3r results and serves them via a web interface.

• Location: finder-backend/
• Port: 3000
• Technology: Go with Fiber web framework
• Function: Runs subdomain enumeration and serves results via API

• Location: finder-frontend/
• Port: 3001 (default React port)
• Technology: React.js
• Function: Provides user interface to interact with the backend

1. User Input: User enters a domain in the React frontend
2. API Request: Frontend sends POST request to http://localhost:3000/find
3. Backend Processing:
   • Runs Subfinder: subfinder -d domain -silent
   • Runs Sublist3r: python sublist3r.py -d domain
   • Combines results: combined := append(subfinderResults, sublist3rFiltered...)
   • Deduplicates: combined_subs := deduplicate(combined)
4. API Response: Backend returns combined_subs as JSON array
5. Frontend Display: React receives and displays the subdomains

• POST /find - Main endpoint for subdomain enumeration
• GET /api/subdomains/:domain - Alternative GET endpoint
• GET /health - Health check endpoint

cd finder-backend
go mod tidy
go run main.go

cd finder-frontend
npm install
npm start

• Frontend: http://localhost:3001
• Backend API: http://localhost:3000

[
  "sub1.example.com",
  "sub2.example.com",
  "sub3.example.com",
  "www.example.com",
  "mail.example.com"
]

Update these paths in finder-backend/main.go:

pythonPath := "/Users/name/Desktop/folder/Sublist3r/venv/bin/python" // your python env location
sublist3rPath := "/Users/name/Desktop/folder/Sublist3r" // sublist3r tool location

The frontend is configured to call http://localhost:3000/find by default.

• Go 1.21+
• Fiber v2.52.0
• Subfinder (external tool)
• Sublist3r (external tool)

• React 19.1.0
• React DOM 19.1.0
• React Scripts 5.0.1

• Combined Enumeration: Uses both Subfinder and Sublist3r
• Deduplication: Removes duplicate subdomains
• Real-time Results: Shows results as they're found
• Error Handling: Graceful error handling and user feedback
• CORS Enabled: Frontend can communicate with backend
• Responsive UI: Modern, user-friendly interface

1. User enters domain in the React frontend
2. Frontend sends request to Go backend via Fiber API
3. Backend runs Subfinder to find subdomains
4. Backend runs Sublist3r to find additional subdomains
5. Backend combines results using the combined_subs variable
6. Backend returns JSON array of unique subdomains
7. Frontend displays results in a clean, organized list

The combined_subs variable contains the final deduplicated list of all subdomains found by both tools, which is then sent to the frontend for display.