btw, link:
https://github.com/mleku/realy/blob/dev/cmd/realy/app/config.go
this is the code for it, you just change the config struct to fit your needs, the rest handles loading the .env file
and this:
https://github.com/mleku/realy/blob/dev/cmd/realy/main.go#L33
handles the help flag to print the usage description for all the keys