Error Handling in Node.js: The Missing Guide Most Node.js tutorials skip error handling. Here's everything you need to know to stop your app from crashing silently. The Golden Rule Never let an error go unhandled. Unhandled errors in Node.js crash your process. In production, that means downtime. Level 1: Synchronous Errors // try/catch works for synchronous code try { const data = JSON . parse ( input ); // Can throw SyntaxError const result = data . items . map ( i => i . id ); // Can throw TypeError } catch ( err ) { console . error ( ' Parse failed: ' , err . message ); // Recover gracefully } Enter fullscreen mode Exit fullscreen mode Simple. Boring. But what about async code? Level 2: Promise Errors // ❌ This error is SILENTLY lost fetch ( ' /api/data ' ) . then ( res => res . json ()) . then ( data => process ( data )); // If process() throws, nobody catches it // ✅ Always add .catch() fetch ( ' /api/data ' ) . then ( res => res . json ()) . then ( data => process ( data )) .…