diff --git a/emmental.py b/emmental.py
index 826fe71..b4c48fd 100755
--- a/emmental.py
+++ b/emmental.py
@@ -3,5 +3,26 @@
 import lib
 lib.settings.load()
 
+import db
 import ui
-ui.Application.run()
+from gi.repository import Gtk
+
+class Application(Gtk.Application):
+    def __init__(self, *args, **kwargs):
+        app_id = f"org.gtk.emmental{'-debug' if __debug__ else ''}"
+        Gtk.Application.__init__(self, *args, application_id=app_id, **kwargs)
+
+    def do_startup(self):
+        Gtk.Application.do_startup(self)
+        self.add_window(ui.window.Window())
+
+    def do_activate(self):
+        for window in self.get_windows():
+            window.present()
+
+    def do_shutdown(self):
+        Gtk.Application.do_shutdown(self)
+        db.sql.optimize()
+
+if __name__ == "__main__":
+    Application().run()
diff --git a/ui/__init__.py b/ui/__init__.py
index 52927a5..8c977a2 100644
--- a/ui/__init__.py
+++ b/ui/__init__.py
@@ -1,24 +1,3 @@
 # Copyright 2021 (c) Anna Schumaker.
 from . import icons
 from . import window
-from gi.repository import Gtk
-import audio
-import db
-
-class EmmentalApplication(Gtk.Application):
-    def __init__(self, *args, **kwargs):
-        Gtk.Application.__init__(self, *args, application_id="org.gtk.emmental", **kwargs)
-
-    def do_activate(self):
-        self.window.present()
-
-    def do_startup(self):
-        self.window = window.Window()
-        Gtk.Application.do_startup(self)
-        self.add_window(self.window)
-
-    def do_shutdown(self):
-        db.sql.optimize()
-        Gtk.Application.do_shutdown(self)
-
-Application = EmmentalApplication()
diff --git a/ui/test_ui.py b/ui/test_ui.py
deleted file mode 100644
index 7e20802..0000000
--- a/ui/test_ui.py
+++ /dev/null
@@ -1,9 +0,0 @@
-# Copyright 2021 (c) Anna Schumaker.
-import unittest
-import ui
-from gi.repository import Gtk
-
-class TestEmmentalApplication(unittest.TestCase):
-    def test_application(self):
-        app = ui.EmmentalApplication()
-        self.assertIsInstance(app, Gtk.Application)