diff --git a/test/EngineTest.cs b/test/EngineTest.cs
index 41604e4..50f2b22 100644
--- a/test/EngineTest.cs
+++ b/test/EngineTest.cs
@@ -232,7 +232,7 @@ namespace Tests
         [Reads(typeof(MockMessage))]
         class ReadMessagesWhenNoneExistEngine : Engine
         {
-            public override void Update(float dt)
+            public override void Update(double dt)
             {
                 emptyReadMessagesResult = ReadMessages<MockMessage>();
             }
@@ -242,7 +242,7 @@ namespace Tests
         public void ReadMessagesWhenNoneHaveBeenEmitted()
         {
             var worldBuilder = new WorldBuilder();
-            worldBuilder.AddEngine<ReadMessagesWhenNoneExistEngine>();
+            worldBuilder.AddEngine(new ReadMessagesWhenNoneExistEngine());
 
             var world = worldBuilder.Build();
 
@@ -440,7 +440,7 @@ namespace Tests
         static Entity entityFromComponentIDResult;
         class GetEntityFromComponentIDEngine : Engine
         {
-            public override void Update(float dt)
+            public override void Update(double dt)
             {
                 var componentID = ReadComponent<MockComponent>().Key;
                 entityFromComponentIDResult = GetEntityByComponentID(componentID);
@@ -451,7 +451,7 @@ namespace Tests
         public void GetEntityFromComponentID()
         {
             var worldBuilder = new WorldBuilder();
-            worldBuilder.AddEngine<GetEntityFromComponentIDEngine>();
+            worldBuilder.AddEngine(new GetEntityFromComponentIDEngine());
 
             MockComponent component;
             component.myInt = 2;
@@ -469,7 +469,7 @@ namespace Tests
         static MockComponent mockComponentByIDResult;
         class GetComponentByIDEngine : Engine
         {
-            public override void Update(float dt)
+            public override void Update(double dt)
             {
                 var componentID = ReadComponent<MockComponent>().Key;
                 mockComponentByIDResult = GetComponentByID<MockComponent>(componentID);
@@ -479,7 +479,7 @@ namespace Tests
         public void GetComponentByID()
         {
             var worldBuilder = new WorldBuilder();
-            worldBuilder.AddEngine<GetComponentByIDEngine>();
+            worldBuilder.AddEngine(new GetComponentByIDEngine());
 
             MockComponent component;
             component.myInt = 2;
@@ -498,7 +498,7 @@ namespace Tests
 
         class GetComponentByIDWithTypeMismatchEngine : Engine
         {
-            public override void Update(float dt)
+            public override void Update(double dt)
             {
                 var componentID = ReadComponent<MockComponent>().Key;
                 GetComponentByID<OtherComponent>(componentID);
@@ -509,7 +509,7 @@ namespace Tests
         public void GetComponentByIDWithTypeMismatch()
         {
             var worldBuilder = new WorldBuilder();
-            worldBuilder.AddEngine<GetComponentByIDWithTypeMismatchEngine>();
+            worldBuilder.AddEngine(new GetComponentByIDWithTypeMismatchEngine());
 
             MockComponent component;
             component.myInt = 2;