Developer builds automated bot to track and alert large Polymarket trades in real time

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A developer has created WhaleTrack, an automated bot that monitors large trades on Polymarket, the prediction market platform, and sends alerts when bets exceed $10,000. The system polls Polymarket's API every five minutes across known high-volume trader wallets and immediately notifies Telegram subscribers, who receive a 10-minute head start before alerts are posted to Twitter. Tweet cards are generated using Puppeteer, which renders an HTML template into a PNG screenshot uploaded via Twitter's media API. The project is built on Node.js and spans roughly 1,200 lines of code, also incorporating Bullpen CLI, the Telegram Bot API, and Vercel for web hosting. The bot is live at whaletrack.app, and the developer noted a key technical hurdle around Twitter's weighted character limit, which was silently truncating posts before a fix was applied.

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