diff --git a/pkgs/development/libraries/libcaca/default.nix b/pkgs/development/libraries/libcaca/default.nix
index 5ff3157272ee..04e1af2326b6 100644
--- a/pkgs/development/libraries/libcaca/default.nix
+++ b/pkgs/development/libraries/libcaca/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, fetchurl, ncurses, zlib, imlib2, pkgconfig, libX11 }:
+{ stdenv, fetchurl, ncurses, zlib, imlib2, pkgconfig, libX11, libXext }:
 
 stdenv.mkDerivation rec {
   name = "libcaca-0.99.beta19";
@@ -13,7 +13,8 @@ stdenv.mkDerivation rec {
 
   outputs = [ "bin" "dev" "out" "man" ];
 
-  propagatedBuildInputs = [ ncurses zlib imlib2 pkgconfig libX11 ];
+  propagatedBuildInputs = [ ncurses zlib imlib2 pkgconfig libX11 ]
+   ++ stdenv.lib.optional stdenv.isDarwin libXext;
 
   postInstall = ''
     mkdir -p $dev/bin
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 3b411cca4a6c..59891d353012 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -7477,7 +7477,7 @@ in
   libburn = callPackage ../development/libraries/libburn { };
 
   libcaca = callPackage ../development/libraries/libcaca {
-    inherit (xlibs) libX11;
+    inherit (xlibs) libX11 libXext;
   };
 
   libcanberra_gtk3 = callPackage ../development/libraries/libcanberra {