WIP: sketch domain data model

deployment/application.nix

@@ -0,0 +1,50 @@
+{
+  lib,
+  ...
+}:
+let
+  inherit (lib) types mkOption;
+in
+{
+  options = {
+    enable = lib.mkEnableOption "Fediversity configuration";
+    applications = mkOption {
+      description = "Collection of NixOS modules, each implementing a Fediversity application";
+      example.hello = {
+        enable = true;
+        module = {pkgs, ...}: {
+          environment.systemPackages = [ pkgs.hello ];
+        };
+      };
+      type = with types; attrsOf (submoduleWith {
+        class = "nixos";
+        description = "A Fediversity application";
+        modules = [
+          (application: {
+            options = {
+              enable = mkOption {
+                type = types.bool;
+              };
+              module = mkOption {
+                default = "The NixOS module to compose into an operator's configuration"
+                type = types.deferredModule;
+              };
+              components = mkOption {
+                type = with types; attrsOf (attrTag {
+                  file-system-state = mkOption {
+                    desciption = "files stored by the application";
+                    type = with types; attrsOf (submodule {
+                      options.minSize = types.bytes;
+                    });
+                    example = {
+                      "/foo/bar/baz" = { minSize = 1024; };
+                    };
+                  };
+                });
+              };
+            };
+          })
+        ];
+      });
+    };
+}

deployment/runtime-environment.nix

@@ -0,0 +1,41 @@
+{
+  lib,
+  ...
+}:
+let
+  inherit (lib) types mkOption;
+in
+{
+  options = {
+    infrastructure = mkOption {
+      description = "Infrastructure for Fediversity applications to run on";
+      type =
+        with types;
+        attrsOf (attrTag {
+
+          single-nixos-machine-via-usb = mkOption {
+            type =
+              with types;
+              submodule {
+                # TODO: maybe steal some data structures from NixOS
+                options = {
+                  hasNetwork = mkOption {
+                    type = types.bool;
+                  };
+                  disks = mkOption {
+                    type =
+                      with types;
+                      attrsOf (submodule {
+                        options.size = mkOption {
+                          type = types.bytes;
+                        };
+
+                      });
+                  };
+                };
+              };
+          };
+        });
+    };
+  };
+}