The init script slightly differs depending on which shell is in use. So for bash it should be in the interactiveShellInit as well. In this case we don't need a mkIf as `bash` is enabled by default on NixOS.
programs.*.interactiveShellInit
`fuck` should only be used for interactive sessions, but nothing more (so init files like `/etc/zshenv` become even more lightweight).
/etc/profile