diff --git a/pkgs/development/libraries/haskell/mwc-random/0.11.0.0.nix b/pkgs/development/libraries/haskell/mwc-random/0.12.0.0.nix
similarity index 84%
rename from pkgs/development/libraries/haskell/mwc-random/0.11.0.0.nix
rename to pkgs/development/libraries/haskell/mwc-random/0.12.0.0.nix
index 5cf459fb0a92..faeb3de2567c 100644
--- a/pkgs/development/libraries/haskell/mwc-random/0.11.0.0.nix
+++ b/pkgs/development/libraries/haskell/mwc-random/0.12.0.0.nix
@@ -2,8 +2,8 @@
 
 cabal.mkDerivation (self: {
   pname = "mwc-random";
-  version = "0.11.0.0";
-  sha256 = "1yqi472m3snx71fvd4mig6my74rkpf3sbsdcmx2y2l00cyk79ghh";
+  version = "0.12.0.0";
+  sha256 = "0c1gzf5nkcbfi2zlhh7ly8b4g2gcr0c1b76awk38g9as9qibgivr";
   buildDepends = [ primitive time vector ];
   meta = {
     homepage = "https://github.com/bos/mwc-random";
diff --git a/pkgs/top-level/haskell-packages.nix b/pkgs/top-level/haskell-packages.nix
index 533173709242..f780f8f10fbf 100644
--- a/pkgs/top-level/haskell-packages.nix
+++ b/pkgs/top-level/haskell-packages.nix
@@ -1020,8 +1020,8 @@ let result = let callPackage = x : y : modifyPrio (newScope result.final x y);
   murmurHash = callPackage ../development/libraries/haskell/murmur-hash {};
 
   mwcRandom_0_10_0_1 = callPackage ../development/libraries/haskell/mwc-random/0.10.0.1.nix {};
-  mwcRandom_0_11_0_0 = callPackage ../development/libraries/haskell/mwc-random/0.11.0.0.nix {};
-  mwcRandom = self.mwcRandom_0_11_0_0;
+  mwcRandom_0_12_0_0 = callPackage ../development/libraries/haskell/mwc-random/0.12.0.0.nix {};
+  mwcRandom = self.mwcRandom_0_12_0_0;
 
   NanoProlog = callPackage ../development/libraries/haskell/NanoProlog {};