nodeenv

NODEENV refers to the environment configuration commonly used by Node.js applications. In practice, the runtime behavior is governed by the environment variable NODE_ENV, a de facto standard for signaling development, testing, or production. The Node.js API does not require this name, but the convention is widely adopted by frameworks, libraries, and deployment pipelines to adapt behavior to the current stage.

Typical values include development, production, and test; some projects also use staging or preview. The chosen value affects logging level, error handling, feature flags, and build optimizations, with frameworks often loading different configurations based on process.env.NODE_ENV.

Setting NODE_ENV varies by platform. On Unix: export NODE_ENV=production; on Windows CMD: set NODE_ENV=production. For cross-platform scripts, tools like cross-env help ensure consistent values across environments.

In code, Node.js reads the value as process.env.NODE_ENV. Example: if (process.env.NODE_ENV === 'production') { /* production optimizations */ }.

The variable influences bundling and runtime behavior, such as Webpack mode, logging verbosity, and connection strings. It enables a single codebase to operate differently depending on environment without code changes.

Best practices include not exposing NODE_ENV in user-facing messages, validating configurations at startup, and documenting expected values for each stage.

See also: Node.js, environment variables, process.env.