diff --git a/pkgs/applications/version-management/monotone-viz/graphviz-2.0.nix b/pkgs/applications/version-management/monotone-viz/graphviz-2.0.nix
index 8ecc5bf9ac8..d7ec4a86463 100644
--- a/pkgs/applications/version-management/monotone-viz/graphviz-2.0.nix
+++ b/pkgs/applications/version-management/monotone-viz/graphviz-2.0.nix
@@ -2,8 +2,6 @@
 , yacc, libtool, fontconfig, pango, gd, libwebp
 }:
 
-assert libpng != null && libjpeg != null && expat != null;
-
 stdenv.mkDerivation rec {
   name = "graphviz-2.0";