Configuration: does Phoenix support "system tuples" like {:system "ENV_VAR"}?

[7stud]

Not exactly sure what what you mean by “system tuples”

I put an example in the title, e.g. : {:system, "PORT}. And system tuples are mentioned both in questions/answers on this forum, e.g.

What is the difference between using {:system, "PORT"} and System.get_env("PORT") in deployment?

I notice that config/*.exs have http: [port: {:system, "PORT"}] but I know that I can do this ,too System.get_env("PORT"). What is the benefit of first one and the second one.

Mix config evolutions

I am opening this thread to discuss the global problems and solutions around the current mix config implementation. As seen in multiple github issues and in multiple places around this forum, the current configuration behaviour via mix config.exs has it’s issues. The most common ones being: Confusion as config being compile time, including reading the environment {system, "MYENV"} being somewhat present but considered bad practice by @josevalim Difficulties around secret handling No standa…

and in articles on configuring phoenix/mix projects, e.g.:

Configuring Elixir Libraries | Michał Muskała

but in what way does System.get_env/2 fall short?

It retrieves the environment variables from the system on which the project is compiled–not from the system on which the project is run?