diff --git a/pkgs/applications/science/math/cntk/default.nix b/pkgs/applications/science/math/cntk/default.nix
index b8e3f2e31e12..07740f4c8aea 100644
--- a/pkgs/applications/science/math/cntk/default.nix
+++ b/pkgs/applications/science/math/cntk/default.nix
@@ -42,10 +42,10 @@ in stdenv.mkDerivation rec {
     "--with-boost=${boost.dev}"
     "--with-protobuf=${protobuf}"
     "--with-mpi=${openmpi}"
-  ] ++ lib.optionals cudaSupport [
-    "--cuda=yes"
+    "--cuda=${if cudaSupport then "yes" else "no"}"
     # FIXME
     "--asgd=no"
+  ] ++ lib.optionals cudaSupport [
     "--with-cuda=${cudatoolkit}"
     "--with-gdk-include=${cudatoolkit}/include"
     "--with-gdk-nvml-lib=${nvidia_x11}/lib"