Ok i got my #Fish #FishShell completions running in #NuShell on #NixOS.
We will see if i adapt it as my daily driver, since i hardly use #posix stuff anyway.
If you were struggling like me to configure the completions with #HomeManager, let me know and i will share  the config tomorrow. 

 @1cc11b6f oh please share. I am just trying out nixos and fishconfig is the next item on the list