Node.js

Environment Commands

Configure Node.js runtime behavior with environment variables and flags. Manage NODE_ENV, enable experimental features, and control memory, threading, and network settings.

6 commands

Pro Tips

Use '--env-file=.env' (Node 20+) to load environment variables natively — no dotenv package needed.

Set 'NODE_OPTIONS="--max-old-space-size=4096"' to apply flags globally without modifying scripts.

Use 'NODE_ENV=production' in production — many frameworks optimize behavior and disable debug features.

Common Mistakes

Never store secrets in .env files committed to git. Use .env.local (gitignored) or a secrets manager.

NODE_OPTIONS applies to ALL node processes including build tools. Overly aggressive flags can break tools.

Commands

Set NODE_ENV

$ NODE_ENV=production node app.js

Run with production environment.

Set NODE_OPTIONS

$ NODE_OPTIONS='--inspect --max-old-space-size=4096' node app.js

Pass CLI flags via environment variable.

Show version

$ node -v

Print Node.js version.

Check syntax

$ node -c app.js

Check syntax without executing.

Show V8 options

$ node --v8-options

List all V8 command-line options.

Enable source maps

$ node --enable-source-maps app.js

Enable source map support in stack traces.