diff --git a/pkgs/development/compilers/chez/default.nix b/pkgs/development/compilers/chez/default.nix
index a02256697daf..82035e456341 100644
--- a/pkgs/development/compilers/chez/default.nix
+++ b/pkgs/development/compilers/chez/default.nix
@@ -5,13 +5,13 @@
 
 stdenv.mkDerivation rec {
   pname = "chez-scheme";
-  version = "9.5.4";
+  version = "9.5.6";
 
   src = fetchFromGitHub {
     owner  = "cisco";
     repo   = "ChezScheme";
     rev    = "refs/tags/v${version}";
-    sha256 = "065dir19cqpn0d1bk9w49wnwzn6qfrgvcqw8da2fdhkafhfcb1bj";
+    sha256 = "sha256-1C5fEbVIpFXlDQ5wFmYZ2nrDUq9jBmvnku/7f0MH7vc=";
     fetchSubmodules = true;
   };