diff --git a/craft_application/application.py b/craft_application/application.py
index 5411313e..ab854327 100644
--- a/craft_application/application.py
+++ b/craft_application/application.py
@@ -47,7 +47,7 @@ class _Dispatcher(craft_cli.Dispatcher):
     @property
     def parsed_args(self) -> argparse.Namespace:
         """The map of parsed command-line arguments."""
-        return self._parsed_command_args
+        return self._parsed_command_args or argparse.Namespace()
 
 
 @final
@@ -61,7 +61,7 @@ class AppMetadata:
     source_ignore_patterns: list[str] = field(default_factory=lambda: [])
     managed_instance_project_path = pathlib.PurePosixPath("/root/project")
 
-    ProjectClass: type[models.Project] = models.Project
+    ProjectClass: type[models.Project] = field(init=False)
 
     def __post_init__(self) -> None:
         setter = super().__setattr__
@@ -129,7 +129,7 @@ def cache_dir(self) -> str:
         # xdg types: https://github.com/python/typeshed/pull/10163
         return save_cache_path(self.app.name)  # type: ignore[no-any-return]
 
-    def _configure_services(self, build_for: str) -> None:
+    def _configure_services(self, build_for: str | None) -> None:
         """Configure additional keyword arguments for any service classes.
 
         Any child classes that override this must either call this directly or must
diff --git a/tests/conftest.py b/tests/conftest.py
index fc689113..07e3a4be 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -33,7 +33,7 @@
 
 class MyProject(craft_application.models.Project):
     def get_build_plan(self) -> list[models.BuildInfo]:
-        arch = craft_application.util.get_host_architecture()
+        arch = util.get_host_architecture()
         return [models.BuildInfo(arch, arch, bases.BaseName("ubuntu", "22.04"))]