diff --git a/src/rigidbody.h b/src/rigidbody.h
index 045bf68..bb0b6e5 100644
--- a/src/rigidbody.h
+++ b/src/rigidbody.h
@@ -6,15 +6,16 @@
 #include "list.h"
 
 struct Collision;
-
 typedef struct RigidBody RigidBody;
+typedef void (*CollisionHandlerFn)(void* obj, List* collisions);
 
 // Referenced transform is stored but not owned by the rigidbody.
 extern RigidBody* rigidbody_make(Transformable transform);
 extern void rigidbody_destroy(RigidBody* self);
 
 extern void rigidbody_add_contact(RigidBody* self, struct Collision hit);
-extern void rigidbody_solve_contacts(RigidBody* self);
+extern void rigidbody_handle_contacts(RigidBody* self);
+extern void rigidbody_solve_contacts(RigidBody* self, List* contacts);
 
 extern void rigidbody_apply_physics(RigidBody* self);