_: prevpkgs: {
  chickenPackages_5 = prevpkgs.chickenPackages_5.overrideScope (_: prevchicken: {
    chickenEggs = prevchicken.chickenEggs.overrideScope (_: preveggs: {
      r7rs = preveggs.r7rs.overrideAttrs (o: {
        patches = (o.patches or []) ++ [ ./r7rs.patch ];
      });

      socket = preveggs.socket.overrideAttrs (o: {
        preBuild = null;
        postPatch = "echo 'touch socket-config' >> build-socket-config";
      });
    });
  });
}