FATAL ERROR: Reached heap limit Allocation failed - JavaScript heap out of memory

Node process hit the V8 heap limit (default ~2GB on 32-bit, ~4GB on 64-bit). 1. Raise the limit: `NODE_OPTIONS=--max-old-space-size=8192 node script.js` (8 GB). 2. For npm scripts: `"build": "NODE_OPTIONS=--max-old-space-size=8192 next build"`. 3. Long-term: profile with --heap-prof, look for leaks, stream large data instead of loading into memory.