node --max-old-space-size: Fix Heap OOM

V8 caps the old-space heap; large builds can exceed it and crash.

"JavaScript heap out of memory" in CI usually means the build needs more heap than V8’s default. Raise it via NODE_OPTIONS, but make sure the runner actually has the RAM.

Common usage

--max-old-space-size=4096 - 4 GB heap (MB)
set globally: NODE_OPTIONS=--max-old-space-size=4096
must be <= the runner’s physical RAM

Example in CI

Give the build more heap.

shell

NODE_OPTIONS=--max-old-space-size=4096 npm run build

In CI

Raising the heap above available RAM just trades a V8 OOM for an OS OOM-kill (exit 137). Right-size the runner. Managed runners like Latchkey offer larger-RAM options and auto-retry transient OOM-kills.

Key takeaways

Raise heap via NODE_OPTIONS.
Heap must fit the runner’s RAM.
Too high trades V8 OOM for exit 137.