Everything Looked Fine Until Memory Ran Out in Our Node.js App

An unexpected memory leak in a Node.js application was discovered during a code freeze, with symptoms including crashing services and unusual memory patterns. The issue was traced back to incorrect file permissions preventing log flushing to disk, causing logs to accumulate in memory. The team used tools like Chrome DevTools and heap snapshots to diagnose and resolve the leak, leading to stabilized memory usage and improved system stability.