diff --git a/pkgs/tools/security/thc-hydra/default.nix b/pkgs/tools/security/thc-hydra/default.nix
index a7b6a96261f0..7222cc81780e 100644
--- a/pkgs/tools/security/thc-hydra/default.nix
+++ b/pkgs/tools/security/thc-hydra/default.nix
@@ -23,6 +23,8 @@ stdenv.mkDerivation rec {
       --replace "-lcurses" "-lncurses"
   '';
 
+  env.NIX_CFLAGS_COMPILE = lib.optionalString stdenv.isDarwin "-Wno-undef-prefix";
+
   nativeBuildInputs = lib.optionals withGUI [ pkg-config makeWrapper ];
 
   buildInputs = [
@@ -45,6 +47,5 @@ stdenv.mkDerivation rec {
     license = licenses.agpl3Plus;
     maintainers = with maintainers; [ offline ];
     platforms = platforms.unix;
-    badPlatforms = platforms.darwin; # fails to build since v9.5
   };
 }