diff --git a/pkgs/development/libraries/x264/default.nix b/pkgs/development/libraries/x264/default.nix
index f857b2a0b89e..91e8a435db80 100644
--- a/pkgs/development/libraries/x264/default.nix
+++ b/pkgs/development/libraries/x264/default.nix
@@ -1,40 +1,29 @@
 { stdenv
 , lib
 , fetchFromGitLab
-, fetchpatch
 , nasm
 , enableShared ? !stdenv.hostPlatform.isStatic
 }:
 
 stdenv.mkDerivation rec {
   pname = "x264";
-  version = "unstable-2021-06-13";
+  version = "0-unstable-2023-10-01";
 
   src = fetchFromGitLab {
     domain = "code.videolan.org";
     owner = "videolan";
     repo = pname;
-    rev = "5db6aa6cab1b146e07b60cc1736a01f21da01154";
-    sha256 = "0swyrkz6nvajivxvrr08py0jrfcsjvpxw78xm1k5gd9xbdrxvknh";
+    rev = "31e19f92f00c7003fa115047ce50978bc98c3a0d";
+    hash = "sha256-7/FaaDFmoVhg82BIhP3RbFq4iKGNnhviOPxl3/8PWCM=";
   };
 
-  # Upstream ./configure greps for (-mcpu|-march|-mfpu) in CFLAGS, which in nix
-  # is put in the cc wrapper anyway.
   patches = [
+    # Upstream ./configure greps for (-mcpu|-march|-mfpu) in CFLAGS, which in nix
+    # is put in the cc wrapper anyway.
     ./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 .
-  ''
-  # Darwin uses `llvm-strip`, which results in a crash at runtime in assembly-based routines when `-x` is specified.
-  + lib.optionalString stdenv.isDarwin ''
+  postPatch = lib.optionalString stdenv.isDarwin ''
     substituteInPlace Makefile --replace '$(if $(STRIP), $(STRIP) -x $@)' '$(if $(STRIP), $(STRIP) -S $@)'
   '';
 
@@ -53,6 +42,12 @@ stdenv.mkDerivation rec {
     ++ lib.optional (!stdenv.isi686) "--enable-pic"
     ++ lib.optional (stdenv.buildPlatform != stdenv.hostPlatform) "--cross-prefix=${stdenv.cc.targetPrefix}";
 
+  makeFlags = [
+    "BASHCOMPLETIONSDIR=$(out)/share/bash-completion/completions"
+    "install-bashcompletion"
+    "install-lib-shared"
+  ];
+
   nativeBuildInputs = lib.optional stdenv.hostPlatform.isx86 nasm;
 
   meta = with lib; {