It probably broke by the latest glib update.
@ -108,6 +108,8 @@ stdenv.mkDerivation rec {
"--install-roboto-font"
] ++ optional optimizationSupport "--optimization";
NIX_CFLAGS_COMPILE = [ "-fpermissive" ];
meta = with lib; {
description = "A virtual guitar amplifier for Linux running with JACK";
longDescription = ''