diff --git a/pkgs/development/interpreters/cg3/default.nix b/pkgs/development/interpreters/cg3/default.nix
index 7f7a38185f9e..8aa0d412c1cf 100644
--- a/pkgs/development/interpreters/cg3/default.nix
+++ b/pkgs/development/interpreters/cg3/default.nix
@@ -10,13 +10,13 @@
 
 let cg3 = stdenv.mkDerivation rec {
   pname = "cg3";
-  version = "1.3.7";
+  version = "1.3.9";
 
   src = fetchFromGitHub {
     owner = "GrammarSoft";
     repo = "${pname}";
     rev = "v${version}";
-    sha256 = "Ena3dGoZsXOIY6mbvnfI0H7QqRifoxWIBKQrK3yQSmY=";
+    sha256 = "sha256-TiEhhk90w5GibGZ4yalIf+4qLA8NoU6+GIPN6QNTz2A=";
   };
 
   nativeBuildInputs = [