diff --git a/src/flecs-cs b/src/flecs-cs
index 2e82db1..a204798 160000
--- a/src/flecs-cs
+++ b/src/flecs-cs
@@ -1 +1 @@
-Subproject commit 2e82db165948e073b813ac712bedd00c70627d03
+Subproject commit a2047983917aa462a8c2f34d5315aea48502f4d8
diff --git a/src/gaemstone/ECS/Filter.cs b/src/gaemstone/ECS/Filter.cs
index c62f02a..a1cf8bf 100644
--- a/src/gaemstone/ECS/Filter.cs
+++ b/src/gaemstone/ECS/Filter.cs
@@ -25,7 +25,7 @@ public unsafe sealed class Filter
 	public static void RunOnce(Universe universe, Delegate action)
 	{
 		var gen  = IterActionGenerator.GetOrBuild(universe, action.Method);
-		var desc = new FilterDesc(gen.Terms.ToArray()) { Name = action.Method.Name };
+		var desc = new FilterDesc(gen.Terms.ToArray());
 		using var filter = new Filter(universe, desc);
 		foreach (var iter in filter.Iter()) gen.RunWithTryCatch(action.Target, iter);
 	}
@@ -48,12 +48,6 @@ public class FilterDesc
 
 	public string? Expression { get; }
 
-	/// <summary>
-	/// Optional name of filter, used for debugging. If a filter is created
-	/// for a system, the provided name should match the system name.
-	/// </summary>
-	public string? Name { get; set; }
-
 	/// <summary>
 	/// When true, terms returned by an iterator may either contain 1 or N
 	/// elements, where terms with N elements are owned, and terms with 1
@@ -63,6 +57,11 @@ public class FilterDesc
 	/// </summary>
 	public bool Instanced { get; set; }
 
+	/// <summary>
+	/// Entity associated with query (optional).
+	/// </summary>
+	public Entity Entity { get; set; }
+
 	public FilterDesc(params Term[] terms)
 		=> Terms = terms;
 	public FilterDesc(string expression) : this()
@@ -71,9 +70,9 @@ public class FilterDesc
 	public unsafe ecs_filter_desc_t ToFlecs(IAllocator allocator)
 	{
 		var desc = new ecs_filter_desc_t {
-			name = allocator.AllocateCString(Name),
-			expr = allocator.AllocateCString(Expression),
+			expr      = allocator.AllocateCString(Expression),
 			instanced = Instanced,
+			entity    = Entity,
 		};
 		var span = desc.terms;
 		if (Terms.Count > span.Length) {
diff --git a/src/gaemstone/ECS/Observer.cs b/src/gaemstone/ECS/Observer.cs
index ae001d1..6f6b9d1 100644
--- a/src/gaemstone/ECS/Observer.cs
+++ b/src/gaemstone/ECS/Observer.cs
@@ -20,12 +20,12 @@ public class ObserverAttribute<TEvent> : ObserverAttribute
 public static class ObserverExtensions
 {
 	public static unsafe EntityRef RegisterObserver(this Universe universe,
-		FilterDesc filter, Entity @event, Action<Iterator> callback)
+		string? name, FilterDesc filter, Entity @event, Action<Iterator> callback)
 	{
 		using var alloc = TempAllocator.Use();
 		var desc = new ecs_observer_desc_t {
 			filter = filter.ToFlecs(alloc),
-			entity = universe.New((filter.Name != null) ? new(filter.Name) : null).Build(),
+			entity = universe.New((name != null) ? EntityPath.Parse(name) : null).Build(),
 			binding_ctx = (void*)CallbackContextHelper.Create((universe, callback)),
 			callback = new() { Data = new() { Pointer = &Callback } },
 		};
@@ -55,9 +55,8 @@ public static class ObserverExtensions
 			iterAction = iter => gen.RunWithTryCatch(instance, iter);
 		}
 
-		filter.Name = method.Name;
 		var @event  = universe.LookupOrThrow(attr.Event);
-		return universe.RegisterObserver(filter, @event, iterAction);
+		return universe.RegisterObserver(method.Name, filter, @event, iterAction);
 	}
 
 	[UnmanagedCallersOnly]
diff --git a/src/gaemstone/ECS/System.cs b/src/gaemstone/ECS/System.cs
index b708e2a..4f3d490 100644
--- a/src/gaemstone/ECS/System.cs
+++ b/src/gaemstone/ECS/System.cs
@@ -30,12 +30,12 @@ public class ExpressionAttribute : Attribute
 public static class SystemExtensions
 {
 	private static unsafe EntityRef RegisterSystem(this Universe universe,
-		QueryDesc query, Entity phase, CallbackContext callback)
+		string? name, QueryDesc query, Entity phase, CallbackContext callback)
 	{
 		using var alloc = TempAllocator.Use();
 		var desc = new ecs_system_desc_t {
-			query = query.ToFlecs(alloc),
-			entity = universe.New((query.Name != null) ? new(query.Name) : null)
+			query  = query.ToFlecs(alloc),
+			entity = universe.New((name != null) ? EntityPath.Parse(name) : null)
 			                 .Add<DependsOn>(phase).Add(phase).Build(),
 			binding_ctx = (void*)CallbackContextHelper.Create(callback),
 			// TODO: Use binding_ctx_free to remove clear the context.
@@ -59,9 +59,9 @@ public static class SystemExtensions
 			callback = iter => gen.RunWithTryCatch(action.Target, iter);
 		}
 
-		query.Name = action.Method.Name;
 		var phase  = universe.LookupOrThrow(attr?.Phase ?? typeof(SystemPhase.OnUpdate));
-		return universe.RegisterSystem(query, phase, new(universe, action.Method, callback));
+		return universe.RegisterSystem(action.Method.Name,
+			query, phase, new(universe, action.Method, callback));
 	}
 
 	public static EntityRef RegisterSystem(this Universe universe,
@@ -83,9 +83,9 @@ public static class SystemExtensions
 			callback = iter => gen.RunWithTryCatch(instance, iter);
 		}
 
-		query.Name = method.Name;
 		var phase  = universe.LookupOrThrow(attr?.Phase ?? typeof(SystemPhase.OnUpdate));
-		return universe.RegisterSystem(query, phase, new(universe, method, callback));
+		return universe.RegisterSystem(method.Name,
+			query, phase, new(universe, method, callback));
 	}
 
 	private class CallbackContext