diff --git a/pkgs/development/compilers/open-watcom/v2.nix b/pkgs/development/compilers/open-watcom/v2.nix
index da63df43d59b..6cb5c6dcc105 100644
--- a/pkgs/development/compilers/open-watcom/v2.nix
+++ b/pkgs/development/compilers/open-watcom/v2.nix
@@ -1,6 +1,7 @@
 { stdenv
 , lib
 , fetchFromGitHub
+, unstableGitUpdater
 
 # Docs cause an immense increase in build time, up to 2 additional hours
 , withDocs ? false
@@ -11,14 +12,14 @@
 
 stdenv.mkDerivation rec {
   pname = "open-watcom-v2";
-  version = "unstable-2021-11-30";
+  version = "unstable-2021-12-10";
   name = "${pname}-unwrapped-${version}";
 
   src = fetchFromGitHub {
     owner = "open-watcom";
     repo = "open-watcom-v2";
-    rev = "982c958eb4840e1c6a98773ba0600f652500f5a7";
-    sha256 = "18dp9nd1gjnpd1870149v67vzxbna25l6zi052z1r51xvaqwc3cx";
+    rev = "ca685c1b780149f7210426f0bb78dd7b67b19e6d";
+    sha256 = "1nmmj94z5hips2426rcdqdcsm8015jjj51rm9fnx81qagdj52j5d";
   };
 
   postPatch = ''
@@ -82,6 +83,10 @@ stdenv.mkDerivation rec {
   # Stripping breaks many tools
   dontStrip = true;
 
+  passthru.updateScript = unstableGitUpdater {
+    url = "https://github.com/open-watcom/open-watcom-v2.git";
+  };
+
   meta = with lib; {
     description = "The v2 fork of the Open Watcom suite of compilers and tools";
     longDescription = ''