diff --git a/pkgs/development/libraries/haskell/monad-par/0.3.4.nix b/pkgs/development/libraries/haskell/monad-par/0.3.4.1.nix
similarity index 90%
rename from pkgs/development/libraries/haskell/monad-par/0.3.4.nix
rename to pkgs/development/libraries/haskell/monad-par/0.3.4.1.nix
index 342bea47f6b..3fc819542eb 100644
--- a/pkgs/development/libraries/haskell/monad-par/0.3.4.nix
+++ b/pkgs/development/libraries/haskell/monad-par/0.3.4.1.nix
@@ -6,8 +6,8 @@
 
 cabal.mkDerivation (self: {
   pname = "monad-par";
-  version = "0.3.4";
-  sha256 = "1j1xskd8smpfi2dpiwnpwakw0hs0i2yn1lrs9l06wz4b148hwc4k";
+  version = "0.3.4.1";
+  sha256 = "0v0gnxzv49zvmgm2cb20dlb8m7mn4chpwrc61g4zp69nabjpwwm8";
   buildDepends = [
     abstractDeque abstractPar deepseq monadParExtras mtl mwcRandom
     parallel
diff --git a/pkgs/top-level/haskell-packages.nix b/pkgs/top-level/haskell-packages.nix
index 4ffd314f3c9..45e0b723d5c 100644
--- a/pkgs/top-level/haskell-packages.nix
+++ b/pkgs/top-level/haskell-packages.nix
@@ -1258,8 +1258,8 @@ let result = let callPackage = x : y : modifyPrio (newScope result.final x y);
   monadLogger = callPackage ../development/libraries/haskell/monad-logger {};
 
   monadPar_0_1_0_3 = callPackage ../development/libraries/haskell/monad-par/0.1.0.3.nix {};
-  monadPar_0_3_4 = callPackage ../development/libraries/haskell/monad-par/0.3.4.nix {};
-  monadPar = self.monadPar_0_3_4;
+  monadPar_0_3_4_1 = callPackage ../development/libraries/haskell/monad-par/0.3.4.1.nix {};
+  monadPar = self.monadPar_0_3_4_1;
 
   monadParExtras = callPackage ../development/libraries/haskell/monad-par-extras {};