Reading the comments, may be it is worth clarifying: this allows macOS users with nix package manager to install brew cask (I.e. typically GUI program that companies releases as pkg or dmg, etc., such as Mathematica, GitHub Desktop, Adobe CC…) without having brew at all.
I.e. it “steals” those brew cask formula and automatically repackage them as nix packages.
A closely related usage would be macOS with nix with nix-darwin, and using nix-darwin config to includes brew casks. This way, nix-darwin assumes brew exists and uses brew to install those casks.
This does have a major distinction on where the applications actually located, where some applications would upset if it is not inside /Applications.
I.e. it “steals” those brew cask formula and automatically repackage them as nix packages.
A closely related usage would be macOS with nix with nix-darwin, and using nix-darwin config to includes brew casks. This way, nix-darwin assumes brew exists and uses brew to install those casks.
This does have a major distinction on where the applications actually located, where some applications would upset if it is not inside /Applications.