diff --git a/flake.nix b/flake.nix
index 162d43b7f88be08e37abc6da31e91a58d4e7c372..70311cc62c6e854d6354060b08c099499d566024 100644
--- a/flake.nix
+++ b/flake.nix
@@ -54,6 +54,10 @@
       url = "github:ndmitchell/hlint";
       flake = false;
     };
+    hnix = {
+      url = "github:milloni/hnix?ref=milloni/horizon";
+      flake = false;
+    };
     lint-utils.url = "git+https://gitlab.homotopic.tech/nix/lint-utils";
     memory = {
       url = "github:parsonsmatt/hs-memory/0f760c8ba0b7d5aacf04a7294e87e5e4fff53f40";
diff --git a/overlay.nix b/overlay.nix
index 66640866bdfff82b1a28021375692103257c4c74..55e8289402f3a96a740aef5c3e202729a27405ba 100644
--- a/overlay.nix
+++ b/overlay.nix
@@ -177,6 +177,8 @@ final: prev: with pkgs.haskell.lib; {
 
   hlint = prev.callCabal2nix "hlint" inputs.hlint { };
 
+  hnix = doJailbreak (dontCheck (prev.callCabal2nix "hnix" inputs.hnix { }));
+
   hourglass = dontCheck (prev.callHackage "hourglass" "0.2.12" { });
 
   hslua-aeson = doJailbreak (prev.callHackage "hslua-aeson" "2.2.1" { });