Building a Whale Alert System for Solana in Node.js

What Are Whale Alerts? Whale alerts track large token movements on-chain. When a wallet moves millions of dollars worth of SOL or tokens, it often signals upcoming price action. Building It Here's the core architecture for a Solana whale tracker in Node.js: const { Connection , PublicKey } = require ( ' @solana/web3.js ' ); const WHALE_THRESHOLD_SOL = 100 ; // Alert on 100+ SOL movements const WATCHED_WALLETS = new Map (); // wallet -> label async function monitorWallet ( connection , wallet , label ) { const pubkey = new PublicKey ( wallet ); connection . onAccountChange ( pubkey , async ( accountInfo ) => { const balanceSOL = accountInfo . lamports / 1 e9 ; console . log ( `[WHALE] ${ label } : Balance changed to ${ balanceSOL } SOL` ); // Check recent transactions const sigs = await connection . getSignaturesForAddress ( pubkey , { limit : 1 }); if ( sigs . length > 0 ) { const tx = await connection . getParsedTransaction ( sigs [ 0 ]. signature ); analyzeTransaction ( tx , label );