diff --git a/horizon.dhall b/horizon.dhall
index 45c7504050bb9f634bdeb5e4dda9291755061f20..6dd688b6f0a68ffe9729c2a174bee70550714092 100644
--- a/horizon.dhall
+++ b/horizon.dhall
@@ -995,6 +995,7 @@ let packages =
           H.callHackage "test-framework-quickcheck2" "0.3.0.5"
       , test-framework-smallcheck =
           H.callHackage "test-framework-smallcheck" "0.2"
+      , testing-feat = H.callHackage "testing-feat" "1.1.1.1"
       , testing-type-modifiers =
           H.callHackage "testing-type-modifiers" "0.1.0.1"
       , texmath = H.callHackage "texmath" "0.12.5.4"
diff --git a/initial-packages.nix b/initial-packages.nix
index 2e7c9397139ab373960190e17c1e016909695150..7358862a93d0bd6e2981bb1b97b436b57634bd47 100644
--- a/initial-packages.nix
+++ b/initial-packages.nix
@@ -1637,6 +1637,8 @@ self: with pkgs.haskell.lib; {
 
   test-framework-th = self.callPackage (./pkgs/test-framework-th.nix) { };
 
+  testing-feat = self.callPackage (./pkgs/testing-feat.nix) { };
+
   testing-type-modifiers = self.callPackage (./pkgs/testing-type-modifiers.nix) { };
 
   texmath = self.callPackage (./pkgs/texmath.nix) { };
diff --git a/pkgs/testing-feat.nix b/pkgs/testing-feat.nix
new file mode 100644
index 0000000000000000000000000000000000000000..c4d7ce033ebf53e948b113b52b5ecf34d90610dd
--- /dev/null
+++ b/pkgs/testing-feat.nix
@@ -0,0 +1,32 @@
+{ mkDerivation
+, QuickCheck
+, base
+, lib
+, size-based
+, testing-type-modifiers
+}:
+mkDerivation {
+  pname = "testing-feat";
+  version = "1.1.1.1";
+  sha256 = "c2c988b816b62c1e16ed611cccfbe7b1f4c53ab650b320bb193ccefc58a4a691";
+  isLibrary = true;
+  isExecutable = false;
+  enableSeparateDataOutput = false;
+  libraryHaskellDepends = [
+    base
+    QuickCheck
+    size-based
+    testing-type-modifiers
+  ];
+  enableLibraryProfiling = true;
+  enableExecutableProfiling = true;
+  doHaddock = false;
+  jailbreak = true;
+  doCheck = false;
+  doBenchmark = false;
+  hyperlinkSource = false;
+  homepage = "https://github.com/size-based/testing-feat";
+  description = "Functional Enumeration of Algebraic Types";
+  license = lib.licenses.bsd3;
+  broken = false;
+}