diff --git a/pkgs/development/tools/parsing/happy/1.19.4.nix b/pkgs/development/tools/parsing/happy/1.19.4.nix
new file mode 100644
index 00000000000..c1dee08c5cc
--- /dev/null
+++ b/pkgs/development/tools/parsing/happy/1.19.4.nix
@@ -0,0 +1,18 @@
+{ cabal, mtl, perl }:
+
+cabal.mkDerivation (self: {
+  pname = "happy";
+  version = "1.19.4";
+  sha256 = "0vcklr1y6yjf8z4wip4al2zw4qlfxcahbdxwpf6c9y31dkv9kr3b";
+  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 0eec1ef0bed..6a18ca30e55 100644
--- a/pkgs/top-level/haskell-packages.nix
+++ b/pkgs/top-level/haskell-packages.nix
@@ -2749,7 +2749,8 @@ self : let callPackage = x : y : modifyPrio (newScope self x y); in
   happy_1_18_11 = callPackage ../development/tools/parsing/happy/1.18.11.nix {};
   happy_1_19_2 = callPackage ../development/tools/parsing/happy/1.19.2.nix {};
   happy_1_19_3 = callPackage ../development/tools/parsing/happy/1.19.3.nix {};
-  happy = self.happy_1_19_3;
+  happy_1_19_4 = callPackage ../development/tools/parsing/happy/1.19.4.nix {};
+  happy = self.happy_1_19_4;
 
   happyMeta = callPackage ../development/tools/haskell/happy-meta {};