add forgejo microvm

hosts/forgejo/default.nix

@@ -0,0 +1,77 @@
+{ config, lib, ... }:
+let
+  mac = "02:00:00:00:00:05";
+in
+{
+  imports = [
+    ./forgejo.nix
+  ];
+  sops.defaultSopsFile = ./secrets.yaml;
+  sops.age.sshKeyPaths = [ "/etc/ssh/ssh_host_ed25519_key" ];
+
+  sops.secrets = {
+    "wg/0xa-proxy" = {
+      owner = config.users.users.systemd-network.name;
+    };
+  };
+
+  microvm = {
+    hypervisor = "qemu";
+    mem = 3 * 1024;
+    vcpu = 2;
+    interfaces = [
+      {
+        type = "tap";
+        id = "uvm-forgejo";
+        mac = mac;
+      }
+    ];
+    shares =
+      [
+        {
+          source = "/nix/store";
+          mountPoint = "/nix/.ro-store";
+          tag = "store";
+          proto = "virtiofs";
+          socket = "store.socket";
+        }
+      ]
+      ++ map
+        (dir: {
+          source = dir;
+          mountPoint = "/${dir}";
+          tag = dir;
+          proto = "virtiofs";
+          socket = "${dir}.socket";
+        })
+        [
+          "etc"
+          "var"
+          "home"
+        ];
+  };
+
+  networking.useNetworkd = true;
+  networking.firewall.enable = lib.mkForce false; # firewalling done by the host
+
+  systemd.network = {
+    enable = true;
+    networks."11-host" = {
+      matchConfig.MACAddress = mac;
+      networkConfig = {
+        Address = "10.99.99.15/24";
+        DHCP = "no";
+      };
+      routes = [
+        {
+          Gateway = "10.99.99.1";
+          Destination = "0.0.0.0/0";
+          Metric = 1024;
+        }
+      ];
+    };
+  };
+
+  networking.hostName = "forgejo";
+  system.stateVersion = "24.11";
+}