diff --git a/pkgs/development/tools/parsing/happy/1.18.11.nix b/pkgs/development/tools/parsing/happy/1.18.11.nix
new file mode 100644
index 000000000000..41f6d5c49a4b
--- /dev/null
+++ b/pkgs/development/tools/parsing/happy/1.18.11.nix
@@ -0,0 +1,18 @@
+{ cabal, mtl, perl }:
+
+cabal.mkDerivation (self: {
+  pname = "happy";
+  version = "1.18.11";
+  sha256 = "1hssiihzl7xipmn5bz71q30wbq2sj92lh2f7z4jarckhldwcqfi9";
+  isLibrary = false;
+  isExecutable = true;
+  buildDepends = [ mtl ];
+  buildTools = [ perl ];
+  meta = {
+    homepage = "http://www.haskell.org/happy/";
+    description = "Happy is a parser generator for Haskell";
+    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 e38fff602424..bc65f251a7ee 100644
--- a/pkgs/top-level/haskell-packages.nix
+++ b/pkgs/top-level/haskell-packages.nix
@@ -176,7 +176,7 @@ let result = let callPackage = x : y : modifyPrio (newScope result.finalReturn x
     cabalInstall = self.cabalInstall_1_18_0_1;
     alex         = self.alex_3_0_5;
     haddock      = self.haddock_2_13_2;
-    happy        = self.happy_1_18_10;
+    happy        = self.happy_1_18_11;
     primitive    = self.primitive_0_5_0_1;      # semi-official, but specified
   };
 
@@ -2343,7 +2343,8 @@ let result = let callPackage = x : y : modifyPrio (newScope result.finalReturn x
   happy_1_18_8 = callPackage ../development/tools/parsing/happy/1.18.8.nix {};
   happy_1_18_9 = callPackage ../development/tools/parsing/happy/1.18.9.nix {};
   happy_1_18_10 = callPackage ../development/tools/parsing/happy/1.18.10.nix {};
-  happy = self.happy_1_18_10;
+  happy_1_18_11 = callPackage ../development/tools/parsing/happy/1.18.11.nix {};
+  happy = self.happy_1_18_11;
 
   happyMeta = callPackage ../development/tools/haskell/happy-meta {};