diff --git a/encompass-cs/Collections/TypedComponentStore.cs b/encompass-cs/Collections/TypedComponentStore.cs
index 9e02b46..2b47f63 100644
--- a/encompass-cs/Collections/TypedComponentStore.cs
+++ b/encompass-cs/Collections/TypedComponentStore.cs
@@ -34,6 +34,7 @@ namespace Encompass
         {
             if (!priorities.ContainsKey(entity) || priority < priorities[entity]) {
                 store[entity] = component;
+                priorities[entity] = priority;
                 return true;
             }
 
diff --git a/encompass-cs/ComponentUpdateManager.cs b/encompass-cs/ComponentUpdateManager.cs
index 3f27029..c61955c 100644
--- a/encompass-cs/ComponentUpdateManager.cs
+++ b/encompass-cs/ComponentUpdateManager.cs
@@ -38,12 +38,15 @@ namespace Encompass
             existingComponentStore.Set(entity, component);
         }
 
-        internal void AddPendingComponent<TComponent>(Entity entity, TComponent component, int priority) where TComponent : struct, IComponent
+        internal bool AddPendingComponent<TComponent>(Entity entity, TComponent component, int priority) where TComponent : struct, IComponent
         {
             if (pendingComponentStore.Set(entity, component, priority))
             {
                 RegisterExistingOrPendingComponentMessage(entity, component);
+                return true;
             }
+
+            return false;
         }
 
         private void RegisterExistingOrPendingComponentMessage<TComponent>(Entity entity, TComponent component) where TComponent : struct, IComponent
@@ -52,9 +55,9 @@ namespace Encompass
             UpToDateComponentStore.Set(entity, component);
         }
 
-        public void UpdateComponent<TComponent>(Entity entity, TComponent component, int priority) where TComponent : struct, IComponent
+        public bool UpdateComponent<TComponent>(Entity entity, TComponent component, int priority) where TComponent : struct, IComponent
         {
-            UpToDateComponentStore.Set<TComponent>(entity, component, priority);
+            return UpToDateComponentStore.Set<TComponent>(entity, component, priority);
         }
 
         // general component reads by type
@@ -90,7 +93,7 @@ namespace Encompass
 
         internal (Entity, TComponent) ReadFirstPendingComponentByType<TComponent>() where TComponent : struct, IComponent
         {
-            if (!SomeExistingComponent<TComponent>()) { throw new Exceptions.NoComponentOfTypeException($"No Component with type {typeof(TComponent)} exists"); }
+            if (!SomePendingComponent<TComponent>()) { throw new Exceptions.NoComponentOfTypeException($"No Component with type {typeof(TComponent)} exists"); }
             return ReadPendingComponentsByType<TComponent>().First();
         }
 
diff --git a/encompass-cs/Engine.cs b/encompass-cs/Engine.cs
index 268be45..3c359dd 100644
--- a/encompass-cs/Engine.cs
+++ b/encompass-cs/Engine.cs
@@ -22,6 +22,7 @@ namespace Encompass
         internal readonly HashSet<Type> writeTypes = new HashSet<Type>();
         internal readonly HashSet<Type> writePendingTypes = new HashSet<Type>();
         internal readonly Dictionary<Type, int> writePriorities = new Dictionary<Type, int>();
+        internal readonly int defaultWritePriority = 0;
 
         /// <summary>
         /// If false, the Engine will ignore time dilation.
@@ -51,6 +52,13 @@ namespace Encompass
                 writePendingTypes = activatesAttribute.writePendingTypes;
             }
 
+            var defaultWritePriorityAttribute = GetType().GetCustomAttribute<DefaultWritePriority>(false);
+
+            if (defaultWritePriorityAttribute != null)
+            {
+                defaultWritePriority = defaultWritePriorityAttribute.writePriority;
+            }
+
             foreach (var writesAttribute in GetType().GetCustomAttributes<Writes>(false))
             {
                 writeTypes.UnionWith(writesAttribute.writeTypes);
@@ -397,23 +405,24 @@ namespace Encompass
         /// </exception>
         protected void SetComponent<TComponent>(Entity entity, TComponent component) where TComponent : struct, IComponent
         {
-            var priority = writePriorities.ContainsKey(typeof(TComponent)) ? writePriorities[typeof(TComponent)] : 0;
+            var priority = writePriorities.ContainsKey(typeof(TComponent)) ? writePriorities[typeof(TComponent)] : defaultWritePriority;
 
             if (!writeTypes.Contains(typeof(TComponent)))
             {
                 throw new IllegalWriteException("Engine {0} tried to update undeclared Component {1}", GetType().Name, typeof(TComponent).Name);
             }
 
+            bool written;
             if (writePendingTypes.Contains(typeof(TComponent)))
             {
-                AddPendingComponent(entity, component, priority);
+                written = AddPendingComponent(entity, component, priority);
             }
             else
             {
-                componentUpdateManager.UpdateComponent(entity, component, priority);
+                written = componentUpdateManager.UpdateComponent(entity, component, priority);
             }
 
-            if (component is IDrawableComponent drawableComponent)
+            if (written && component is IDrawableComponent drawableComponent)
             {
                 componentManager.RegisterDrawableComponent(entity, component, drawableComponent.Layer);
             }
@@ -471,9 +480,9 @@ namespace Encompass
             componentUpdateManager.AddExistingComponent(entity, component);
         }
 
-        internal void AddPendingComponent<TComponent>(Entity entity, TComponent component, int priority) where TComponent : struct, IComponent
+        internal bool AddPendingComponent<TComponent>(Entity entity, TComponent component, int priority) where TComponent : struct, IComponent
         {
-            componentUpdateManager.AddPendingComponent<TComponent>(entity, component, priority);
+            return componentUpdateManager.AddPendingComponent<TComponent>(entity, component, priority);
         }
 
         /// <summary>
diff --git a/encompass-cs/WorldBuilder.cs b/encompass-cs/WorldBuilder.cs
index 09ed567..925dbf4 100644
--- a/encompass-cs/WorldBuilder.cs
+++ b/encompass-cs/WorldBuilder.cs
@@ -131,7 +131,7 @@ namespace Encompass
                 senders.Add(engine);
             }
 
-            foreach (var componentType in engine.readTypes.Union(engine.writeTypes))
+            foreach (var componentType in engine.readTypes.Union(engine.writeTypes).Union(engine.readPendingTypes))
             {
                  RegisterComponent(componentType);
             }
diff --git a/test/WorldBuilderTest.cs b/test/WorldBuilderTest.cs
index da93315..8e75f8a 100644
--- a/test/WorldBuilderTest.cs
+++ b/test/WorldBuilderTest.cs
@@ -223,14 +223,14 @@ namespace Tests
             [Receives(typeof(SetMessage))]
             [Writes(typeof(AComponent))]
             [WritesPending(typeof(AComponent))]
-            [Encompass.DefaultWritePriority(1)]
+            [Encompass.DefaultWritePriority(4)]
             class AEngine : Engine
             {
                 public override void Update(double dt)
                 {
                     foreach (var setMessage in ReadMessages<SetMessage>())
                     {
-                        SetComponent(setMessage.entity, new AComponent { myInt = 0 });
+                        SetComponent(setMessage.entity, new AComponent { myInt = 5 });
                     }
                 }
             }
@@ -250,6 +250,20 @@ namespace Tests
                 }
             }
 
+            [Receives(typeof(SetMessage))]
+            [Writes(typeof(AComponent), 2)]
+            [WritesPending(typeof(AComponent))]
+            class CEngine : Engine
+            {
+                public override void Update(double dt)
+                {
+                    foreach (var setMessage in ReadMessages<SetMessage>())
+                    {
+                        SetComponent(setMessage.entity, new AComponent { myInt = 3 });
+                    }
+                }
+            }
+
             static AComponent resultComponent;
 
             [ReadsPending(typeof(AComponent))]
@@ -267,6 +281,8 @@ namespace Tests
                 var worldBuilder = new WorldBuilder();
                 worldBuilder.AddEngine(new AEngine());
                 worldBuilder.AddEngine(new BEngine());
+                worldBuilder.AddEngine(new CEngine());
+                worldBuilder.AddEngine(new ReadComponentEngine());
 
                 var entity = worldBuilder.CreateEntity();
                 worldBuilder.SendMessage(new SetMessage { entity = entity });
@@ -275,7 +291,7 @@ namespace Tests
 
                 world.Update(0.01);
 
-                Assert.That(resultComponent.myInt, Is.EqualTo(0));
+                Assert.That(resultComponent.myInt, Is.EqualTo(3));
             }
         }