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Built a fully automated crypto arbitrage scanner that monitors 5 major exchanges simultaneously every 10 seconds across 20 top coins, firing instant Telegram alerts when a price spread exceeds 1.5%.
The system fetches live prices concurrently from Binance, Coinbase, Kraken, KuCoin, and OKX using async HTTP requests, calculates spreads across every exchange pair in real time, and delivers formatted alerts with exact buy/sell prices and estimated profit per $1,000 invested.
Key engineering highlights:
· Async architecture (Python asyncio + aiohttp) for concurrent exchange polling with zero blocking
· On-chain payment verification - subscribers pay in USDT/USDC and the bot verifies the transaction directly on Polygon/BSC via block explorer APIs, no payment processor needed
· Telegram subscription bot with full admin controls, auto invite link generation, and renewal handling
· Live web dashboard (Flask + Chart.js) showing real-time spreads, alert history, and revenue stats
· Deployed on Railway with persistent storage, graceful shutdown handling, and health check endpoints
Tech stack: Python · asyncio · aiohttp · python-telegram-bot v20 · Flask · SQLite · Railway
The network for creativity
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Creatives on Contra have earned over $150M and we are just getting started
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