diff --git a/flake.lock b/flake.lock
index 8b88a15..32c4dd7 100644
--- a/flake.lock
+++ b/flake.lock
@@ -52,16 +52,16 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1716361217,
-        "narHash": "sha256-mzZDr00WUiUXVm1ujBVv6A0qRd8okaITyUp4ezYRgc4=",
+        "lastModified": 1718835956,
+        "narHash": "sha256-wM9v2yIxClRYsGHut5vHICZTK7xdrUGfrLkXvSuv6s4=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "46397778ef1f73414b03ed553a3368f0e7e33c2f",
+        "rev": "dd457de7e08c6d06789b1f5b88fc9327f4d96309",
         "type": "github"
       },
       "original": {
         "id": "nixpkgs",
-        "ref": "nixos-23.11",
+        "ref": "nixos-24.05",
         "type": "indirect"
       }
     },
diff --git a/flake.nix b/flake.nix
index f0e0199..478e95b 100644
--- a/flake.nix
+++ b/flake.nix
@@ -1,7 +1,7 @@
 {
   description = "Lenticular cloud interface";
   inputs = {
-    nixpkgs.url = "nixpkgs/nixos-23.11";
+    nixpkgs.url = "nixpkgs/nixos-24.05";
     flake-utils.url = "github:numtide/flake-utils";
     flake-compat = { # for shell.nix
       url = "github:edolstra/flake-compat";
diff --git a/lenticular_cloud/views/auth.py b/lenticular_cloud/views/auth.py
index 160aadd..2752d5b 100644
--- a/lenticular_cloud/views/auth.py
+++ b/lenticular_cloud/views/auth.py
@@ -113,7 +113,7 @@ async def login() -> ResponseReturnValue:
     options = webauthn.generate_authentication_options(
         rp_id = public_url.hostname,
         user_verification = UserVerificationRequirement.REQUIRED,
-        challenge=webauthn.helpers.generate_challenge(32)
+        challenge=webauthn.helpers.generate_challenge()
     )
     token = jwt.encode({
             'challenge': b64encode(options.challenge).decode(),