diff --git a/pkgs/development/libraries/haskell/monad-par/0.3.4.1.nix b/pkgs/development/libraries/haskell/monad-par/0.3.4.1.nix
deleted file mode 100644
index 3fc819542eb4..000000000000
--- a/pkgs/development/libraries/haskell/monad-par/0.3.4.1.nix
+++ /dev/null
@@ -1,28 +0,0 @@
-{ cabal, abstractDeque, abstractPar, deepseq, HUnit, monadParExtras
-, mtl, mwcRandom, parallel, QuickCheck, testFramework
-, testFrameworkHunit, testFrameworkQuickcheck2, testFrameworkTh
-, time
-}:
-
-cabal.mkDerivation (self: {
-  pname = "monad-par";
-  version = "0.3.4.1";
-  sha256 = "0v0gnxzv49zvmgm2cb20dlb8m7mn4chpwrc61g4zp69nabjpwwm8";
-  buildDepends = [
-    abstractDeque abstractPar deepseq monadParExtras mtl mwcRandom
-    parallel
-  ];
-  testDepends = [
-    abstractDeque abstractPar deepseq HUnit monadParExtras mtl
-    mwcRandom QuickCheck testFramework testFrameworkHunit
-    testFrameworkQuickcheck2 testFrameworkTh time
-  ];
-  doCheck = false;
-  meta = {
-    homepage = "https://github.com/simonmar/monad-par";
-    description = "A library for parallel programming based on a monad";
-    license = self.stdenv.lib.licenses.bsd3;
-    platforms = self.ghc.meta.platforms;
-    maintainers = [ self.stdenv.lib.maintainers.andres ];
-  };
-})
diff --git a/pkgs/top-level/haskell-packages.nix b/pkgs/top-level/haskell-packages.nix
index 90918c536386..82154f85ef99 100644
--- a/pkgs/top-level/haskell-packages.nix
+++ b/pkgs/top-level/haskell-packages.nix
@@ -1377,7 +1377,6 @@ 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_1 = callPackage ../development/libraries/haskell/monad-par/0.3.4.1.nix {};
   monadPar_0_3_4_2 = callPackage ../development/libraries/haskell/monad-par/0.3.4.2.nix {};
   monadPar = self.monadPar_0_3_4_2;