Http request via proxy when scripting

I would like evaluate elixir for scripting and followed the samples here: [Single File Elixir Scripts · The Phoenix Files]

and stuck there because i am behind a proxy when accessing the www.
I can curl the requested endpoint successfully .

For a better understanding some questions:

  1. Does elixir (scripts …) is checking /using the common http(s)_proxy env var under linux like other tools?
  2. If 1. is not the case: How do i setup the proxy setting for the req “package” or do I have to change the http client ?
  3. Is user auth. for the proxy server supported and is there a special syntax to enter user name and password ?