diff --git a/pkgs/data/icons/numix-icon-theme-square/default.nix b/pkgs/data/icons/numix-icon-theme-square/default.nix
index ac42bc32169..198229cce37 100644
--- a/pkgs/data/icons/numix-icon-theme-square/default.nix
+++ b/pkgs/data/icons/numix-icon-theme-square/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, fetchFromGitHub, numix-icon-theme }:
+{ stdenv, fetchFromGitHub, gtk3, numix-icon-theme }:
 
 stdenv.mkDerivation rec {
   name = "${package-name}-${version}";
@@ -12,15 +12,19 @@ stdenv.mkDerivation rec {
     sha256 = "1gjwc0s6a7q1jby5bcwxkcmbs470m81y8s0clsm0qhcmcn1c36xj";
   };
 
-  buildInputs = [ numix-icon-theme ];
-
-  dontBuild = true;
+  nativeBuildInputs = [ gtk3 numix-icon-theme ];
 
   installPhase = ''
     mkdir -p $out/share/icons
     cp -a Numix-Square{,-Light} $out/share/icons/
   '';
 
+  postFixup = ''
+    for theme in $out/share/icons/*; do
+      gtk-update-icon-cache $theme
+    done
+  '';
+
   meta = with stdenv.lib; {
     description = "Numix icon theme (square version)";
     homepage = https://numixproject.org;