diff --git a/pkgs/applications/misc/font-manager/default.nix b/pkgs/applications/misc/font-manager/default.nix
index 5df34c84f09..5d0854a4c72 100644
--- a/pkgs/applications/misc/font-manager/default.nix
+++ b/pkgs/applications/misc/font-manager/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, fetchFromGitHub, meson, ninja, gettext, python3,
+{ stdenv, fetchFromGitHub, meson, ninja, gettext, python3, fetchpatch,
   pkgconfig, libxml2, json-glib , sqlite, itstool, librsvg,
   vala, gtk3, gnome3, desktop-file-utils, wrapGAppsHook, gobject-introspection
 }:
@@ -42,6 +42,15 @@ stdenv.mkDerivation rec {
     "-Ddisable_pycompile=true"
   ];
 
+  patches = [
+    # fix build with Vala 0.46
+    (fetchpatch {
+      url = "https://github.com/FontManager/font-manager/commit/c73b40de11f376f4515a0edfe97fb3721a264b35.patch";
+      sha256 = "0lacwsifgvda2r3z6j2a0svdqr6mgav7zkvih35xa8155y8wfpnw";
+      excludes = [ "fedora/font-manager.spec" ];
+    })
+  ];
+
   postPatch = ''
     chmod +x meson_post_install.py
     patchShebangs meson_post_install.py