In my config I have this;
config :my_app, MyApp.MyEmailer,
# ...............
password: System.get_env("MY_ENV"), # returns nil
# password: 123456789, # this works
In my ~/.bash_profile I have:
MY_ENV="123456789"
And:
$ source ~/.bash_profile
$ echo $MY_ENV
123456789
$ # running phoenix here. ....
MacOS