--- a/rust/hwphysics/src/common.rs	Fri Nov 09 01:05:34 2018 +0300
+++ b/rust/hwphysics/src/common.rs	Fri Nov 09 03:36:21 2018 +0300
@@ -1,1 +1,10 @@
-pub type GearId = u16;
\ No newline at end of file
+pub type GearId = u16;
+pub trait GearData {}
+
+pub trait GearDataProcessor<T: GearData> {
+    fn add(&mut self, gear_id: GearId, gear_data: T);
+}
+
+pub trait GearDataAggregator<T: GearData> {
+    fn find_processor(&mut self) -> &mut GearDataProcessor<T>;
+}