diff --git a/flake.lock b/flake.lock
index 6800461..99f93a3 100644
--- a/flake.lock
+++ b/flake.lock
@@ -192,6 +192,22 @@
         "type": "github"
       }
     },
+    "nixos-2405": {
+      "locked": {
+        "lastModified": 1731386116,
+        "narHash": "sha256-lKA770aUmjPHdTaJWnP3yQ9OI1TigenUqVC3wweqZuI=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "689fed12a013f56d4c4d3f612489634267d86529",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-24.05",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
     "nixos-hardware": {
       "locked": {
         "lastModified": 1731797098,
@@ -324,6 +340,7 @@
         "lanzaboote": "lanzaboote",
         "mysecrets": "mysecrets",
         "nix-darwin": "nix-darwin",
+        "nixos-2405": "nixos-2405",
         "nixos-hardware": "nixos-hardware",
         "nixos-unstable": "nixos-unstable",
         "nixpkgs": "nixpkgs_2",
diff --git a/flake.nix b/flake.nix
index 0fac46e..fddebc0 100644
--- a/flake.nix
+++ b/flake.nix
@@ -3,6 +3,7 @@
 
   inputs = {
     nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.11";
+    nixos-2405.url = "github:NixOS/nixpkgs/nixos-24.05";
     nixos-unstable.url = "github:NixOS/nixpkgs/nixos-unstable";
     nixos-hardware.url = "github:NixOS/nixos-hardware/master";
     home-manager = {
diff --git a/home/modules/packages.nix b/home/modules/packages.nix
index a164d91..dbc1e22 100644
--- a/home/modules/packages.nix
+++ b/home/modules/packages.nix
@@ -150,7 +150,7 @@ let
     chromium
     falkon
     thunderbird
-    calibre
+    inputs.nixos-unstable.legacyPackages.${system}.calibre   # FIXME: test failure in 24.11
     dino
     zotero
     ding