diff --git a/pkgs/applications/misc/pdfpc/default.nix b/pkgs/applications/misc/pdfpc/default.nix
index 5678cef8e1bd..0fa676bdfb4b 100644
--- a/pkgs/applications/misc/pdfpc/default.nix
+++ b/pkgs/applications/misc/pdfpc/default.nix
@@ -1,6 +1,6 @@
 { lib, stdenv, fetchFromGitHub, cmake, pkg-config, vala, gtk3, libgee
 , poppler, libpthreadstubs, gstreamer, gst-plugins-base, gst-plugins-good, gst-libav, gobject-introspection, wrapGAppsHook
-, qrencode, webkitgtk, discount, json-glib }:
+, qrencode, webkitgtk, discount, json-glib, fetchpatch }:
 
 stdenv.mkDerivation rec {
   pname = "pdfpc";
@@ -33,6 +33,16 @@ stdenv.mkDerivation rec {
     json-glib
   ];
 
+  patches = [
+    # needed for compiling pdfpc 4.6.0 with vala 0.56.7, see
+    # https://github.com/pdfpc/pdfpc/issues/686
+    # https://github.com/pdfpc/pdfpc/pull/687
+    (fetchpatch {
+      url = "https://github.com/pdfpc/pdfpc/commit/d38edfac63bec54173b4b31eae5c7fb46cd8f714.diff";
+      hash = "sha256-KC2oyzcwU2fUmxaed8qAsKcePwR5KcXgpVdstJg8KmU=";
+    })
+  ];
+
   cmakeFlags = lib.optional stdenv.isDarwin "-DMOVIES=OFF";
 
   meta = with lib; {