* ```
ismael@flony$ nix-env -i -f foo.nix
warning: unknown setting 'experimental-features'
unpacking 'https://nixos.org/channels/nixpkgs-unstable/nixexprs.tar.xz'...
installing 'tmux-3.1c'
these paths will be fetched (7.53 MiB download, 36.40 MiB unpacked):
(...)
created 38 symlinks in user environment
ismael@flony ~ $ cat foo.nix                                                                                                                                                                                                                  
{ nixpkgs ? import <nixpkgs> {} }:
with nixpkgs;
[
  (assert false; bc)
  tmux
]
```