diff --git a/Makefile b/Makefile
index ca916ab..ae050cc 100644
--- a/Makefile
+++ b/Makefile
@@ -9,7 +9,8 @@ SHELL := $(shell which bash)
 .PHONY: sync
 sync:
 	sudo rsync -a --exclude='hardware-configuration.nix' nixos/ /etc/nixos/
-	sudo nixos-rebuild switch
+	sudo nixos-rebuild switch --flake /etc/nixos#cesium
+	sudo cp /etc/nixos/flake.lock nixos/flake.lock 2>/dev/null || true
 
 
 .PHONY: sync-dry-run
@@ -25,7 +26,9 @@ add-pre-commit-hook:
 
 .PHONY: upgrade
 upgrade:
-	nixos-rebuild switch --upgrade-all --sudo
+	sudo nix flake update /etc/nixos
+	sudo nixos-rebuild switch --flake /etc/nixos#cesium
+	sudo cp /etc/nixos/flake.lock nixos/flake.lock 2>/dev/null || true
 
 .PHONY: cleanup
 cleanup:
diff --git a/nixos/common.nix b/nixos/common.nix
index 096843b..6e95eb2 100644
--- a/nixos/common.nix
+++ b/nixos/common.nix
@@ -112,10 +112,19 @@
   # Enable CUPS to print documents.
   services.printing.enable = true;
 
+  services.flatpak.enable = true;
+  services.flatpak.remotes = [{
+    name = "flathub";
+    location = "https://dl.flathub.org/repo/flathub.flatpakrepo";
+  }];
+  services.flatpak.packages = [
+    { appId = "com.snes9x.Snes9x"; origin = "flathub"; }
+  ];
+
   system.autoUpgrade = {
     enable = true;
     allowReboot = false;
-    channel = "https://channels.nixos.org/nixos-25.11";
+    flake = "/etc/nixos#cesium";
   };
 
   nix.gc = {
diff --git a/nixos/configuration.nix b/nixos/configuration.nix
index 0a929ef..cf3a801 100644
--- a/nixos/configuration.nix
+++ b/nixos/configuration.nix
@@ -1,4 +1,4 @@
-{ config, pkgs, ... }:
+{ config, pkgs, nixpkgs-unstable, ... }:
 
 {
   imports = [
@@ -9,7 +9,6 @@
     ./mounts.nix
     ./services.nix
     ./users/sebastian.nix
-    <home-manager/nixos>
   ];
 
   # Home Manager configuration
@@ -23,11 +22,7 @@
   nixpkgs.config.allowUnfree = true;
   nixpkgs.overlays = [
     (final: prev: {
-      rustdesk-flutter =
-        let
-          unstable = import <nixos-unstable> { config = prev.config; };
-        in
-        unstable.rustdesk-flutter;
+      rustdesk-flutter = nixpkgs-unstable.legacyPackages.${prev.stdenv.hostPlatform.system}.rustdesk-flutter;
     })
   ];
   nix.settings.experimental-features = [ "nix-command" "flakes" ];
diff --git a/nixos/flake.lock b/nixos/flake.lock
new file mode 100644
index 0000000..383b55c
--- /dev/null
+++ b/nixos/flake.lock
@@ -0,0 +1,82 @@
+{
+  "nodes": {
+    "home-manager": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1775425411,
+        "narHash": "sha256-KY6HsebJHEe5nHOWP7ur09mb0drGxYSzE3rQxy62rJo=",
+        "owner": "nix-community",
+        "repo": "home-manager",
+        "rev": "0d02ec1d0a05f88ef9e74b516842900c41f0f2fe",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-community",
+        "ref": "release-25.11",
+        "repo": "home-manager",
+        "type": "github"
+      }
+    },
+    "nix-flatpak": {
+      "locked": {
+        "lastModified": 1768656715,
+        "narHash": "sha256-Sbh037scxKFm7xL0ahgSCw+X2/5ZKeOwI2clqrYr9j4=",
+        "owner": "gmodena",
+        "repo": "nix-flatpak",
+        "rev": "123fe29340a5b8671367055b75a6e7c320d6f89a",
+        "type": "github"
+      },
+      "original": {
+        "owner": "gmodena",
+        "repo": "nix-flatpak",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1776067740,
+        "narHash": "sha256-B35lpsqnSZwn1Lmz06BpwF7atPgFmUgw1l8KAV3zpVQ=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "7e495b747b51f95ae15e74377c5ce1fe69c1765f",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-25.11",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs-unstable": {
+      "locked": {
+        "lastModified": 1775710090,
+        "narHash": "sha256-ar3rofg+awPB8QXDaFJhJ2jJhu+KqN/PRCXeyuXR76E=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "4c1018dae018162ec878d42fec712642d214fdfa",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "home-manager": "home-manager",
+        "nix-flatpak": "nix-flatpak",
+        "nixpkgs": "nixpkgs",
+        "nixpkgs-unstable": "nixpkgs-unstable"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/nixos/flake.nix b/nixos/flake.nix
new file mode 100644
index 0000000..eb02a1f
--- /dev/null
+++ b/nixos/flake.nix
@@ -0,0 +1,25 @@
+{
+  description = "NixOS configuration for cesium";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.11";
+    nixpkgs-unstable.url = "github:NixOS/nixpkgs/nixos-unstable";
+    home-manager = {
+      url = "github:nix-community/home-manager/release-25.11";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+    nix-flatpak.url = "github:gmodena/nix-flatpak";
+  };
+
+  outputs = { self, nixpkgs, nixpkgs-unstable, home-manager, nix-flatpak }: {
+    nixosConfigurations.cesium = nixpkgs.lib.nixosSystem {
+      system = "x86_64-linux";
+      specialArgs = { inherit nixpkgs-unstable; };
+      modules = [
+        ./configuration.nix
+        home-manager.nixosModules.home-manager
+        nix-flatpak.nixosModules.nix-flatpak
+      ];
+    };
+  };
+}
\ No newline at end of file