diff --git a/pkgs/development/libraries/x264/default.nix b/pkgs/development/libraries/x264/default.nix
index df248f6b4d43..153790002390 100644
--- a/pkgs/development/libraries/x264/default.nix
+++ b/pkgs/development/libraries/x264/default.nix
@@ -1,4 +1,4 @@
-{ stdenv, lib, fetchFromGitLab, nasm
+{ stdenv, lib, fetchFromGitLab, fetchpatch, nasm
 , enableShared ? !stdenv.hostPlatform.isStatic
  }:
 
@@ -16,7 +16,15 @@ stdenv.mkDerivation rec {
 
   # Upstream ./configure greps for (-mcpu|-march|-mfpu) in CFLAGS, which in nix
   # is put in the cc wrapper anyway.
-  patches = [ ./disable-arm-neon-default.patch ];
+  patches = [
+    ./disable-arm-neon-default.patch
+    (fetchpatch {
+      # https://code.videolan.org/videolan/x264/-/merge_requests/114
+      name = "fix-parallelism.patch";
+      url = "https://code.videolan.org/videolan/x264/-/commit/e067ab0b530395f90b578f6d05ab0a225e2efdf9.patch";
+      hash = "sha256-16h2IUCRjYlKI2RXYq8QyXukAdfoQxyBKsK/nI6vhRI=";
+    })
+  ];
 
   postPatch = ''
     patchShebangs .