Biljakt

A tool for finding and ranking used cars from Blocket.se. It scrapes car listings, enriches each one with vehicle history data from Biluppgifter.se, and presents them in a scored, filterable web UI.

How it works

1. Scraper — given a Blocket search URL, paginates through all results and fetches each listing's details.
2. Enrichment — for every car, looks up its registration number on Biluppgifter to get mileage history, market valuation, inspection dates, ownership count, and warning flags.
3. Scoring — the web UI ranks cars using configurable rules (linear interpolation and boolean flags). Rules and weights are editable in the browser and persisted to localStorage.

Setup

Prerequisites: Node.js 18+, an Apify account with API access.

# Install backend dependencies
npm install

# Install frontend dependencies
cd web && npm install && cd ..

Copy .env.example to .env and fill in your Apify token:

cp .env.example .env

Running the scraper

npm run find-cars "https://www.blocket.se/mobility/search/..."

Paste any Blocket car search URL. Results are written to generated/carsData.json.

Note: The scraper caches HTML responses in cache/ to avoid redundant network requests on reruns.

Running the web UI

cd web && npm run dev

Opens at http://localhost:5173. The UI reads generated/carsData.json via the Vite dev server and renders each car ranked by score. Use the sliders icon to open the rules editor.

Project structure

├── src/
│   ├── index.ts           # CLI entry point
│   ├── getAllCars.ts       # Car enrichment and data persistence
│   ├── blocketScraper.ts  # Blocket pagination and list scraping
│   ├── types.ts           # CarData interface
│   ├── bilupgifter/
│   │   ├── getBilupgifterData.ts   # Biluppgifter scraping and parsing
│   │   ├── getMileageConsistency.ts # Linear regression on mileage history
│   │   └── models.ts               # Biluppgifter types
│   └── util/
│       ├── apifyFetch.ts  # Apify-backed fetcher (for bot-protected pages)
│       ├── smartFetch.ts  # Rate-limited fetcher with file cache
│       ├── cache.ts       # Cache key/path utilities
│       └── general.ts     # JSON parse helper
├── web/
│   └── src/
│       ├── App.tsx        # Main layout and data loading
│       ├── CarCard.tsx    # Car tile component
│       ├── RulesModal.tsx # Scoring rules editor
│       ├── scoring.ts     # Scoring engine
│       ├── rules.ts       # Default scoring rules
│       └── types.ts       # Car interface for the UI
├── models.ts              # Zod schemas for Blocket API responses
├── generated/             # Output data (gitignored)
└── cache/                 # HTTP response cache (gitignored)

Scoring rules

Rules are defined in web/src/rules.ts and editable at runtime via the UI.

• Linear rules — map a numeric field to a score via two control points (e.g., 0 km → 30 pts, 230 000 km → 0 pts).
• Flag rules — add or subtract a fixed score when a condition is met (e.g., meter tampering warning → −30 pts).

All rule changes are saved to localStorage and merged with any newly added default rules on next load.