I Built a Self-Hosted Competitor Price Monitor Because SaaS Pricing Is Out of Control
The Problem
I run a small online store. To stay competitive, I needed to track my competitors' pricing. The obvious solution? Sign up for a SaaS price monitoring tool.
Then I saw the prices:
- Prisync: $99/month
- Price2Spy: $20-58/month
- Keepa: $29/month (Amazon only)
For a small operation, $99/month is absurd. So I built my own.
What I Built: MarketEye
MarketEye is a self-hosted competitor price monitor. You run it on your own machine, point it at any product URL, and it tracks price changes automatically.
Tech stack: Python + FastAPI + SQLite + APScheduler
Features:
- Drop any product URL → auto price tracking
- Email + webhook alerts on price changes
- Price history charts + CSV/JSON export
- Works with Amazon, Shopify, JD, Taobao, any HTML page
- Web dashboard included (no CLI needed)
How It Works
- Add a product URL through the web dashboard
- MarketEye scrapes the page at configurable intervals
- When a price changes, you get an alert
- All data stays on your machine - no cloud, no third party
The scraping engine handles various e-commerce platforms out of the box and provides a plugin interface for custom scrapers.
Why Self-Hosted?
- One-time payment: $49 vs $99/month ($3,564 over 3 years)
- Unlimited products: no per-product fees
- Data privacy: your pricing data never leaves your machine
- Customizable: full Python source, extend it however you want
What's Next
I'll be sharing more technical deep-dives on the architecture, scraping challenges, and lessons learned from building and shipping this as a solo developer.
Check it out: MarketEye on Gumroad
Questions and feedback welcome! 🚀