diff --git a/pkgs/development/libraries/haskell/mwc-random/default.nix b/pkgs/development/libraries/haskell/mwc-random/default.nix
index 995571abc20..b8543d2b376 100644
--- a/pkgs/development/libraries/haskell/mwc-random/default.nix
+++ b/pkgs/development/libraries/haskell/mwc-random/default.nix
@@ -4,8 +4,8 @@
 
 cabal.mkDerivation (self: {
   pname = "mwc-random";
-  version = "0.13.1.1";
-  sha256 = "1hi9ci65m3pjkli0rvx2x4fmp73c9fsmnc1zkpaj4g64ibhhir64";
+  version = "0.13.1.2";
+  sha256 = "0b0amp9nv750azg3jc5yyfpdaqzh0z09jp41hwgrzr0j6kq1ygqi";
   buildDepends = [ primitive time vector ];
   testDepends = [
     HUnit QuickCheck statistics testFramework testFrameworkHunit