diff --git a/flake.lock b/flake.lock
index ed3ca791bc1421759975f8d5723f90c59116e1e5..bb364c3fbdbb93844f11b0b16729bad10d866ed5 100644
--- a/flake.lock
+++ b/flake.lock
@@ -106,11 +106,11 @@
         "nixpkgs": "nixpkgs_2"
       },
       "locked": {
-        "lastModified": 1696931656,
-        "narHash": "sha256-n5f2zcYFd8bYdt1yCKsb/dAHvLv2KrGOUrqjVgY7aDo=",
+        "lastModified": 1696939688,
+        "narHash": "sha256-WS86PW3lKYTaZNEWlD37jiiU/OGZbR6s2eQFIkJE7qc=",
         "ref": "refs/heads/master",
-        "rev": "71792f6f7bf1ebcaec123b977eb787059ef1879e",
-        "revCount": 1101,
+        "rev": "19b4b4dbb9f6d5b2a4e99ce1a386818f5e44e51e",
+        "revCount": 1103,
         "type": "git",
         "url": "https://gitlab.horizon-haskell.net/package-sets/horizon-core"
       },
diff --git a/flake.nix b/flake.nix
index 8411995fd44d62596c011ba723014674a6c5de27..270fe47f2792ac6033839b22234b24079f85121c 100644
--- a/flake.nix
+++ b/flake.nix
@@ -31,7 +31,7 @@
     }:
     flake-utils.lib.eachSystem [ "x86_64-linux" ] (system:
     let
-      pkgs = import nixpkgs { inherit system; allowUnfree = true; };
+      pkgs = import nixpkgs { inherit system; config.allowUnfree = true; };
     in
     with pkgs.lib;
     with pkgs.writers;