var
Use strongly typed environment variables like a boss
env-var
Verification, sanitization, and type coercion for environment variables in Node.js
opter
A Node JS wrapper around commander to allow for easy commandline and env var parsing
proxy-from-env
Offers getProxyForUrl to get the proxy URL for a URL, respecting the *_PROXY (e.g. HTTP_PROXY) and NO_PROXY environment variables.