diff --git a/source/application.cpp b/source/application.cpp
index cc1bc73..d0ad292 100644
--- a/source/application.cpp
+++ b/source/application.cpp
@@ -60,6 +60,31 @@ namespace gmtk
 			return {{{(coords[0] - extra) * s, (coords[0] + 1.f + extra) * s}, {(coords[1] - extra) * s, (coords[1] + 1.f + extra) * s}}};
 		}
 
+		location left() const
+		{
+			return {level, {coords[0] - 1, coords[1]}};
+		}
+
+		location right() const
+		{
+			return {level, {coords[0] + 1, coords[1]}};
+		}
+
+		location bottom() const
+		{
+			return {level, {coords[0], coords[1] - 1}};
+		}
+
+		location top() const
+		{
+			return {level, {coords[0], coords[1] + 1}};
+		}
+
+		location moved(geom::vector<int, 2> const & delta) const
+		{
+			return {level, coords + delta};
+		}
+
 		location down() const
 		{
 			return {level + 1, {coords[0] * 3 + 1, coords[1] * 3 + 1}};
@@ -115,9 +140,22 @@ namespace gmtk
 
 		struct location location;
 
-		boost::container::flat_set<ecs::handle> belts = {};
+		boost::container::flat_set<ecs::handle> belts_to = {};
+		boost::container::flat_set<ecs::handle> belts_from = {};
 	};
 
+	void add_belt(ecs::container & world, ecs::handle from, ecs::handle to)
+	{
+		world.get(from).get<path_vertex>().belts_to.insert(to);
+		world.get(to).get<path_vertex>().belts_from.insert(from);
+	}
+
+	void remove_belt(ecs::container & world, ecs::handle from, ecs::handle to)
+	{
+		world.get(from).get<path_vertex>().belts_to.erase(to);
+		world.get(to).get<path_vertex>().belts_from.erase(from);
+	}
+
 	struct occupied
 	{
 		psemek_ecs_declare_uuid("occupied")
@@ -226,6 +264,75 @@ namespace gmtk
 	using index = index_base<vertex, util::make_uuid("vertex_index")>;
 	using path_index = index_base<path_vertex, util::make_uuid("path_vertex_index")>;
 
+	void sink_belt(ecs::container & world, location m)
+	{
+		if (auto entity = world.index<index>().find(m.up()); !entity || !world.get(*entity).contains<zoomer>())
+			return;
+
+		auto & index = world.index<path_index>();
+
+		auto c = m.up().down();
+
+		auto d = m.coords - c.coords;
+
+		auto ce = index.get(c);
+		auto me = index.get(m);
+
+		auto & cv = world.get(ce).get<path_vertex>();
+
+		if (cv.belts_to.contains(me))
+		{
+			auto & mv = world.get(me).get<path_vertex>();
+			auto ne = *mv.belts_to.begin();
+
+			remove_belt(world, ce, me);
+			remove_belt(world, me, ne);
+
+			auto cd = m.down();
+			auto md = cd.moved(d);
+
+			auto cde = index.get(cd);
+			auto mde = index.get(md);
+
+			add_belt(world, cde, mde);
+			add_belt(world, mde, ne);
+
+			sink_belt(world, md);
+		}
+		else if (cv.belts_from.contains(me))
+		{
+			auto & mv = world.get(me).get<path_vertex>();
+			auto ne = *mv.belts_from.begin();
+
+			remove_belt(world, ne, me);
+			remove_belt(world, me, ce);
+
+			auto cd = m.down();
+			auto md = cd.moved(d);
+
+			auto cde = index.get(cd);
+			auto mde = index.get(md);
+
+			add_belt(world, ne, mde);
+			add_belt(world, mde, cde);
+
+			sink_belt(world, md);
+		}
+	}
+
+	void sink(ecs::container & world, location & c, location & m)
+	{
+		if (auto entity = world.index<index>().find(m.up()); !entity || !world.get(*entity).contains<zoomer>())
+			return;
+
+		auto d = m.coords - c.coords;
+
+		c = m.down();
+		m = c.moved(d);
+
+		sink(world, c, m);
+	}
+
 	void generate_next_task(random::generator & rng, map & map)
 	{
 		color type;
@@ -307,7 +414,7 @@ namespace gmtk
 
 		map.world.apply<path_vertex const>([&](path_vertex const & vertex)
 		{
-			for (auto b : vertex.belts)
+			for (auto b : vertex.belts_to)
 			{
 				auto q = map.world.get(b).get<path_vertex const>().location;
 				float w0 = 0.3f * std::pow(3.f, 1.f - vertex.location.level);
@@ -319,7 +426,7 @@ namespace gmtk
 
 		map.world.apply<path_vertex const>([&](path_vertex const & vertex)
 		{
-			for (auto b : vertex.belts)
+			for (auto b : vertex.belts_to)
 			{
 				auto q = map.world.get(b).get<path_vertex const>().location;
 
@@ -381,15 +488,15 @@ namespace gmtk
 		});
 	}
 
-	void draw_selection(location const & l, gfx::painter & painter)
+	void draw_selection(location const & l, gfx::painter & painter, gfx::color_rgba const & color)
 	{
 		auto b = l.bbox();
 		float s = std::pow(3.f, -l.level) * 0.1f;
 
-		painter.line(b.corner(0, 0), b.corner(1, 0), s, {255, 0, 255, 255}, true);
-		painter.line(b.corner(1, 0), b.corner(1, 1), s, {255, 0, 255, 255}, true);
-		painter.line(b.corner(1, 1), b.corner(0, 1), s, {255, 0, 255, 255}, true);
-		painter.line(b.corner(0, 1), b.corner(0, 0), s, {255, 0, 255, 255}, true);
+		painter.line(b.corner(0, 0), b.corner(1, 0), s, color, true);
+		painter.line(b.corner(1, 0), b.corner(1, 1), s, color, true);
+		painter.line(b.corner(1, 1), b.corner(0, 1), s, color, true);
+		painter.line(b.corner(0, 1), b.corner(0, 0), s, color, true);
 	}
 
 	struct application
@@ -474,58 +581,31 @@ namespace gmtk
 							auto d = selected_->coords - belt_start_->coords;
 							if (std::abs(d[0]) + std::abs(d[1]) == 1)
 							{
-								bool from_zoom = false;
-								bool to_zoom = false;
+								auto s = belt_start_->down();
 
-								if (auto entity = map_.world.index<index>().find(*belt_start_))
-									if (map_.world.get(*entity).contains<zoomer>())
-										from_zoom = true;
-								(void)from_zoom;
-
-								if (auto entity = map_.world.index<index>().find(*selected_))
-									if (map_.world.get(*entity).contains<zoomer>())
-										to_zoom = true;
-
-								auto vx = [&](int i)
-								{
-									auto p = belt_start_->down();
-
-									if (i < 2 && from_zoom)
-									{
-										p.coords += d;
-										p = p.down();
-									}
-
-									if (i >= 2 && to_zoom)
-									{
-										p.coords += d;
-										p = p.down();
-									}
-
-									p.coords += d * i;
-
-									return p;
-								};
+								location belt[4];
+								for (int i = 0; i <= 3; ++i)
+									belt[i] = s.moved(d * i);
+								sink(map_.world, belt[0], belt[1]);
+								sink(map_.world, belt[3], belt[2]);
 
 								auto & index = map_.world.index<path_index>();
 								for (int i = 0; i < 3; ++i)
 								{
-									auto p = vx(i);
-									auto q = vx(i + 1);
+									auto p = belt[i];
+									auto q = belt[i + 1];
 
 									auto s = index.get(p);
 									auto t = index.get(q);
 
 									auto & sv = map_.world.get(s).get<path_vertex>();
-									auto & tv = map_.world.get(t).get<path_vertex>();
 
-									if (sv.belts.contains(t))
-										sv.belts.erase(t);
+									if (sv.belts_to.contains(t))
+										remove_belt(map_.world, s, t);
 									else
 									{
-										if (tv.belts.contains(s))
-											tv.belts.erase(s);
-										sv.belts.insert(t);
+										remove_belt(map_.world, t, s);
+										add_belt(map_.world, s, t);
 									}
 								}
 							}
@@ -575,6 +655,13 @@ namespace gmtk
 						vertex{*selected_},
 						zoomer{}
 					);
+
+					auto c = selected_->down();
+
+					sink_belt(map_.world, c.left());
+					sink_belt(map_.world, c.right());
+					sink_belt(map_.world, c.bottom());
+					sink_belt(map_.world, c.top());
 				}
 			}
 
@@ -648,7 +735,7 @@ namespace gmtk
 				{
 					{
 						auto & v = map_.world.get(map_.world.index<path_index>().get(i.start)).get<path_vertex const>();
-						if (!v.belts.contains(i.target))
+						if (!v.belts_to.contains(i.target))
 						{
 							map_.world.detach<occupied>(i.target);
 							map_.world.destroy(entity);
@@ -672,19 +759,10 @@ namespace gmtk
 					map_.world.detach<occupied>(s);
 
 					auto & v = map_.world.get(s).get<path_vertex const>();
-					if (v.belts.empty())
+					if (v.belts_to.empty() && v.belts_from.empty())
 					{
-						bool should_destroy = true;
-						map_.world.apply<path_vertex const>([&](path_vertex const & v){
-							if (v.belts.contains(s))
-								should_destroy = false;
-						});
-
-						if (should_destroy)
-						{
-							map_.world.destroy(entity);
-							return;
-						}
+						map_.world.destroy(entity);
+						return;
 					}
 				}
 
@@ -707,7 +785,7 @@ namespace gmtk
 
 				std::vector<ecs::handle> targets;
 
-				for (auto b : map_.world.get(map_.world.index<path_index>().get(i.start)).get<path_vertex>().belts)
+				for (auto b : map_.world.get(map_.world.index<path_index>().get(i.start)).get<path_vertex>().belts_to)
 					if (!map_.world.get(b).contains<occupied>())
 						targets.push_back(b);
 
@@ -787,7 +865,10 @@ namespace gmtk
 			draw(map_, view_level, painter_);
 
 			if (selected_)
-				draw_selection(*selected_, painter_);
+				draw_selection(*selected_, painter_, {255, 0, 255, 255});
+
+			if (belt_start_)
+				draw_selection(*belt_start_, painter_, {255, 255, 0, 255});
 
 			painter_.render(geom::orthographic_camera{view_box_}.transform());
 		}