{ pkgs }: let self = { example-a = pkgs.callPackage ./example-a { }; example-b = pkgs.callPackage ./example-b { }; pyzotero = pkgs.callPackage ./pyzotero { }; pyzotero-cli = pkgs.callPackage ./pyzotero-cli { pyzotero = self.pyzotero; }; }; in self // { default = self.example-a; }