self: super: let prebuilt = self.stdenv.mkDerivation rec { pname = "iosevka-tv-2"; version = "15.6.3"; src = self.fetchurl { urls = [ "https://c.krebsco.de/iosevka-tv-2-${version}.tar.gz" "https://ni.krebsco.de/~tv/mirrors/iosevka/iosevka-tv-2-${version}.tar.gz" ]; hash = "sha256-W2bOlM0dYKAt+k2OpNJsNx6/hWEItJ2Tob8thtJJ1BA="; }; installPhase = '' mkdir $out mv * $out/ ''; }; in if super.iosevka.version == prebuilt.version then prebuilt else super.iosevka-tv-2