diff --git a/flake.lock b/flake.lock
index d05574b..8d45056 100644
--- a/flake.lock
+++ b/flake.lock
@@ -20,16 +20,16 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1762653957,
-        "narHash": "sha256-3em63zYO+s0NxxKwPXyzV80fXfwZOg7/LjYF5ndZltc=",
+        "lastModified": 1764521362,
+        "narHash": "sha256-M101xMtWdF1eSD0xhiR8nG8CXRlHmv6V+VoY65Smwf4=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "c148fa0cf61fc3bb7b011f2d4f8d789964ea7dd0",
+        "rev": "871b9fd269ff6246794583ce4ee1031e1da71895",
         "type": "github"
       },
       "original": {
         "owner": "NixOS",
-        "ref": "master",
+        "ref": "25.11",
         "repo": "nixpkgs",
         "type": "github"
       }
diff --git a/flake.nix b/flake.nix
index 2a79302..bc6ad79 100644
--- a/flake.nix
+++ b/flake.nix
@@ -1,7 +1,7 @@
 {
   description = "Nix flake for the activity logging script";
   inputs = {
-    nixpkgs.url = "github:NixOS/nixpkgs/master";
+    nixpkgs.url = "github:NixOS/nixpkgs/25.11";
     sudoku-solver.url = "path:./src/sudoku-hs";
   };
   outputs =