diff --git a/flake.lock b/flake.lock
index b014ef0..38aa550 100644
--- a/flake.lock
+++ b/flake.lock
@@ -772,7 +772,7 @@
         "nix-tools": "nix-tools",
         "nixpkgs": [
           "haskell-nix",
-          "nixpkgs-unstable"
+          "nixpkgs-2105"
         ],
         "nixpkgs-2003": "nixpkgs-2003",
         "nixpkgs-2009": "nixpkgs-2009",
diff --git a/flake.nix b/flake.nix
index 0f7d353..6b9f7a5 100644
--- a/flake.nix
+++ b/flake.nix
@@ -4,7 +4,7 @@
   inputs.haskell-nix.url =
     "github:input-output-hk/haskell.nix?rev=4aeeba8d713d0b98c92c8c717df24da17d463c1d";
   inputs.nixpkgs.follows = "haskell-nix/nixpkgs-unstable";
-  inputs.haskell-nix.inputs.nixpkgs.follows = "haskell-nix/nixpkgs-unstable";
+  inputs.haskell-nix.inputs.nixpkgs.follows = "haskell-nix/nixpkgs-2105";
 
   inputs.plutus.url =
     "github:input-output-hk/plutus?rev=65bad0fd53e432974c3c203b1b1999161b6c2dce";