treewide: Refactor in order to clean up flake.nix

flake.nix

@@ -3,12 +3,10 @@
 
   inputs = {
     nixpkgs.url = "github:nixos/nixpkgs/nixos-22.05";
-    nixos-hardware.url = "github:nixos/nixos-hardware/master";
     sops-nix = {
       url = "github:Mic92/sops-nix";
       inputs.nixpkgs.follows = "nixpkgs";
     };
-
     tlaternet-webserver = {
       url = "git+https://gitea.tlater.net/tlaternet/tlaternet.git";
       inputs.nixpkgs.follows = "nixpkgs";
@@ -18,118 +16,97 @@
   outputs = {
     self,
     nixpkgs,
-    nixos-hardware,
     sops-nix,
     tlaternet-webserver,
   }: let
     system = "x86_64-linux";
-
-    overlays = [
-      (final: prev: {
-        local = import ./pkgs {
-          pkgs = prev;
-        };
-      })
-    ];
-
-    pkgs = import nixpkgs {inherit system overlays;};
-    sops-pkgs = sops-nix.packages.${system};
   in {
-    nixosConfigurations = {
-      tlaternet = nixpkgs.lib.nixosSystem {
-        inherit system;
-
-        modules = [
-          ({modulesPath, ...}: {
-            imports = [(modulesPath + "/profiles/headless.nix")];
-            nixpkgs.overlays = overlays;
-          })
-          (import ./modules)
-
-          (import ./configuration)
-          (import ./configuration/linode.nix)
-          (import ./configuration/hardware-configuration.nix)
+    ##################
+    # Configurations #
+    ##################
+    nixosConfigurations = let
+      # Modules that should be generic to all systems
+      genericModule = {...}: {
+        imports = [
+          # Inject flake dependencies
           sops-nix.nixosModules.sops
           tlaternet-webserver.nixosModules.default
+
+          # Import actual configuration
+          (import ./configuration)
+        ];
+      };
+    in {
+      # The actual system definition
+      tlaternet = nixpkgs.lib.nixosSystem {
+        inherit system;
+        modules = [
+          genericModule
+          (import ./configuration/hardware-specific/linode)
         ];
       };
 
+      # A qemu VM to test the above with
       vm = nixpkgs.lib.nixosSystem {
         inherit system;
-
         modules = [
-          ({modulesPath, ...}: {
-            imports = [(modulesPath + "/profiles/headless.nix")];
-            nixpkgs.overlays = overlays;
-          })
-          (import ./modules)
-
-          (import ./configuration)
-          sops-nix.nixosModules.sops
-          tlaternet-webserver.nixosModules.default
-          ({lib, ...}: {
-            users.users.tlater.password = "insecure";
-
-            # Disable graphical tty so -curses works
-            boot.kernelParams = ["nomodeset"];
-
-            # Sets the base domain for nginx to localhost so that we
-            # can easily test locally with the VM.
-            services.nginx.domain = lib.mkOverride 99 "localhost";
-
-            # Use the staging secrets
-            sops.defaultSopsFile = lib.mkOverride 99 ./keys/staging.yaml;
-
-            # # Set up VM settings to match real VPS
-            # virtualisation.memorySize = 3941;
-            # virtualisation.cores = 2;
-          })
+          genericModule
+          (import ./configuration/hardware-specific/vm.nix)
         ];
       };
     };
 
+    ####################
+    # Helper functions #
+    ####################
+    lib = import ./lib {lib = nixpkgs.lib;};
+
+    ####################
+    # VM launch script #
+    ####################
     apps.${system}.default = let
       inherit (self.nixosConfigurations.vm.config.system.build) vm;
       inherit (nixpkgs.legacyPackages.${system}) writeShellScript;
-      inherit (nixpkgs.lib.attrsets) mapAttrsToList;
-      inherit (nixpkgs.lib.strings) concatStringsSep;
-      ports = {
+      qemuNetOpts = self.lib.makeQemuNetOpts {
         "2222" = "2222";
         "3080" = "80";
         "3443" = "443";
-        "2221" = "2221";
         "21025" = "21025"; # Starbound
       };
-      QEMU_NET_OPTS =
-        concatStringsSep ","
-        (mapAttrsToList
-          (host: vm: "hostfwd=::${host}-:${vm}")
-          ports);
     in {
       type = "app";
       program = builtins.toString (writeShellScript "run-vm" ''
         export QEMU_OPTS="-m 3941 -smp 2 -curses"
-        export QEMU_NET_OPTS="${QEMU_NET_OPTS}"
+        export QEMU_NET_OPTS="${qemuNetOpts}"
         "${vm}/bin/run-tlaternet-vm"
       '');
     };
 
-    devShells.${system}.default = pkgs.mkShell {
-      sopsPGPKeyDirs = ["./keys/hosts/" "./keys/users/"];
-      nativeBuildInputs = [
-        sops-pkgs.sops-import-keys-hook
-      ];
-      buildInputs = with pkgs; [
-        nixfmt
-        git-lfs
-        sops-pkgs.sops-init-gpg-key
-      ];
+    ###########################
+    # Development environment #
+    ###########################
+    devShells.${system}.default = let
+      inherit (sops-nix.packages.${system}) sops-import-keys-hook sops-init-gpg-key;
+      deploy-rs-bin = deploy-rs.packages.${system}.default;
+      pkgs = nixpkgs.legacyPackages.${system};
+    in
+      nixpkgs.legacyPackages.${system}.mkShell {
+        sopsPGPKeyDirs = ["./keys/hosts/" "./keys/users/"];
+        nativeBuildInputs = [
+          sops-import-keys-hook
+        ];
+        packages = with pkgs; [
+          nixfmt
+          git-lfs
+          sops-init-gpg-key
+          deploy-rs-bin
+        ];
 
-      shellHook = ''
-        # Work around sudo requiring a full terminal when deploying to
-        # a remote host
-        export NIX_SSHOPTS="-t"
-      '';
-    };
+        shellHook = ''
+          # Work around sudo requiring a full terminal when deploying to
+          # a remote host
+          export NIX_SSHOPTS="-t"
+        '';
+      };
   };
 }