diff --git a/pkgs/development/compilers/gambit/unstable.nix b/pkgs/development/compilers/gambit/unstable.nix
index f98fd5ca935..545bece12c4 100644
--- a/pkgs/development/compilers/gambit/unstable.nix
+++ b/pkgs/development/compilers/gambit/unstable.nix
@@ -1,11 +1,11 @@
 { callPackage, fetchgit }:
 
 callPackage ./build.nix {
-  version = "unstable-2018-03-26";
-  git-version = "4.8.9-8-g793679bd";
+  version = "unstable-2018-05-30";
+  git-version = "4.8.9-54-gffe8841b";
   SRC = fetchgit {
     url = "https://github.com/feeley/gambit.git";
-    rev = "793679bd57eb6275cb06e6570b05f4a78df61bf9";
-    sha256 = "0bippvmrc8vcaa6ka3mhzfgkagb6a1616g7nxk0i0wapxai5cngj";
+    rev = "ffe8841b56330eb86fd794b16dc7f83914ecc7c5";
+    sha256 = "1xzkwa2f6zazybbgd5zynhr36krayhr29vsbras5ld63hkrxrp7q";
   };
 }