1 files changed, 39 insertions, 35 deletions
diff --git a/src/main.rs b/src/main.rs
index dfcf22c..e5076d1 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -61,40 +61,42 @@ fn main() -> Result<(), Box<dyn Error>>
         )
         .init();
 
-    let mut engine = Engine::new();
-
-    engine.spawn((
-        Camera::default(),
-        WorldPosition {
-            position: Vec3 { x: 0.0, y: 0.0, z: 3.0 },
-        },
-        ActiveCamera,
-        FlyCamera::default(),
-    ));
-
-    engine.add_sole(GlobalLight::default())?;
-
-    engine.register_system(*START_PHASE, init);
+    Engine::new()
+        .with_extension(engine::windowing::Extension::default())
+        .with_extension(
+            RenderingExtension::builder()
+                .graphics_props(
+                    GraphicsProperties::builder()
+                        .debug(cfg!(debug_assertions))
+                        .build(),
+                )
+                .build(),
+        )
+        .with_extension(InputExtension::default())
+        .with_extension(FlyCameraExtension(FlyCameraOptions {
+            mouse_sensitivity: 0.2,
+        }))
+        .with_extension(Application)
+        .start();
 
-    engine.add_extension(engine::windowing::Extension::default());
+    Ok(())
+}
 
-    engine.add_extension(
-        RenderingExtension::builder()
-            .graphics_props(
-                GraphicsProperties::builder()
-                    .debug(cfg!(debug_assertions))
-                    .build(),
-            )
-            .build(),
-    );
+struct Application;
 
-    engine.add_extension(FlyCameraExtension(FlyCameraOptions {
-        mouse_sensitivity: 0.2,
-    }));
+impl engine::ecs::extension::Extension for Application
+{
+    fn collect(self, mut collector: engine::ecs::extension::Collector<'_>)
+    {
+        let _ = collector.add_sole(GlobalLight::default());
 
-    engine.add_extension(InputExtension::default());
+        collector.add_system(*START_PHASE, init);
+    }
+}
 
-    engine.spawn((
+fn init(mut assets: Single<Assets>, mut actions: Actions)
+{
+    actions.spawn((
         WindowCreationAttributes::default()
             .with_title("Game")
             .with_cursor_visible(false)
@@ -102,13 +104,15 @@ fn main() -> Result<(), Box<dyn Error>>
         RenderingTargetWindow,
     ));
 
-    engine.start();
-
-    Ok(())
-}
+    actions.spawn((
+        Camera::default(),
+        WorldPosition {
+            position: Vec3 { x: 0.0, y: 0.0, z: 3.0 },
+        },
+        ActiveCamera,
+        FlyCamera::default(),
+    ));
 
-fn init(mut assets: Single<Assets>, mut actions: Actions)
-{
     actions.spawn((
         PointLight::builder()
             .diffuse(YELLOW)