is-env can determine the current JavaScript running environment, and now includes 'browser', 'react-native', 'nodejs'.

Is Env - Environment Detecter

Flexible creation & lookup of global namespaces, e.g. 'development', 'staging', 'stable'

Offers getProxyForUrl to get the proxy URL for a URL, respecting the *_PROXY (e.g. HTTP_PROXY) and NO_PROXY environment variables.

A Babel preset for each environment.

AWS credential provider that sources credentials from known environment variables

Run scripts that set and use environment variables across platforms

Loads environment variables from .env file

Runtime agnostic JS utils

A global executable to run applications with the ENV variables loaded by dotenv

HANDLE CONFIGURATION ONCE AND FOR ALL

A Babel preset that targets modern browsers by fixing engine bugs.

Convert modern CSS into something browsers understand

Uses export conditions to return environment information in a way that works with major bundlers and runtimes.

Executes a command using the environment variables in an env file

Share target browsers between different front-end tools, like Autoprefixer, Stylelint and babel-env-preset

Expand environment variables using dotenv

A library for obtaining browser versions with their maximum supported Baseline feature set and Widely Available status.

Detect Node.JS (as opposite to browser environment). ESM modification

Verification, sanitization, and type coercion for environment variables in Node.js