home-manager correctly sets the following in my configuration
```
  . /nix/store/i5xh8hcsfpw6985rifl7fp4cv8chc214-fzf-0.21.1/share/fzf/completion.zsh
  . /nix/store/i5xh8hcsfpw6985rifl7fp4cv8chc214-fzf-0.21.1/share/fzf/key-bindings.zsh
```