phone: Add working flake

This is a working nix flake I wrote for the PinePhone on the PinePhone.
It successfully updated the system from a 2023-11-15 version to the
latest nixos-unstable release.

phone/configuration.nix

@@ -1,12 +1,6 @@
 { config, lib, pkgs, ... }:
 
 {
-  imports = [
-    (import <mobile-nixos/lib/configuration.nix> { device = "pine64-pinephone"; })
-    ./hardware-configuration.nix
-    <mobile-nixos/examples/phosh/phosh.nix>
-  ];
-
   networking.hostName = "mobile-nixos";
 
   #
@@ -32,6 +26,8 @@
   # It's recommended to keep enabled on these constrained devices
   zramSwap.enable = true;
 
+  nix.settings.experimental-features = [ "nix-command" "flakes" "repl-flake" ];
+
   # Auto-login for phosh
   services.xserver.desktopManager.phosh = {
     user = "user";

phone/flake.lock

@@ -0,0 +1,44 @@
+{
+  "nodes": {
+    "mobile-nixos": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1715627339,
+        "narHash": "sha256-HJ6V7hc64iBqXlZ8kH4sXmUzPH+0Hn6wYURmZmL5LFk=",
+        "owner": "NixOS",
+        "repo": "mobile-nixos",
+        "rev": "655c8830d5fe2eae79c8fc0bab8033b34c8456eb",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "repo": "mobile-nixos",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1718160348,
+        "narHash": "sha256-9YrUjdztqi4Gz8n3mBuqvCkMo4ojrA6nASwyIKWMpus=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "57d6973abba7ea108bac64ae7629e7431e0199b6",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "mobile-nixos": "mobile-nixos",
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

phone/flake.nix

@@ -0,0 +1,29 @@
+{
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+
+    mobile-nixos = {
+      url = "github:NixOS/mobile-nixos";
+      flake = false;
+    };
+  };
+
+  outputs = { self, nixpkgs, mobile-nixos } @ attrs:
+  {
+    nixosConfigurations = {
+      mobile-nixos = nixpkgs.lib.nixosSystem {
+        system = "aarch64-linux";
+        specialArgs = attrs;
+        modules = [
+          (import "${mobile-nixos}/lib/configuration.nix" {
+            device = "pine64-pinephone";
+          })
+
+          ./configuration.nix
+          ./hardware-configuration.nix
+          ./phosh.nix
+        ];
+      };
+    };
+  };
+}

phone/phosh.nix

@@ -0,0 +1,39 @@
+#
+# This file represents safe opinionated defaults for a basic Phosh system.
+#
+# NOTE: this file and any it imports **have** to be safe to import from
+#       an end-user's config.
+#
+{ config, lib, pkgs, options, ... }:
+
+{
+  mobile.beautification = {
+    silentBoot = lib.mkDefault true;
+    splash = lib.mkDefault true;
+  };
+
+  services.xserver.desktopManager.phosh = {
+    enable = true;
+    group = "users";
+  };
+
+  programs.calls.enable = true;
+
+  environment.systemPackages = with pkgs; [
+    chatty              # IM and SMS
+    epiphany            # Web browser
+    gnome-console       # Terminal
+    megapixels          # Camera
+  ];
+
+  hardware.sensor.iio.enable = true;
+
+  assertions = [
+    { assertion = options.services.xserver.desktopManager.phosh.user.isDefined;
+    message = ''
+      `services.xserver.desktopManager.phosh.user` not set.
+        When importing the phosh configuration in your system, you need to set `services.xserver.desktopManager.phosh.user` to the username of the session user.
+    '';
+    }
+  ];
+}