diff --git a/src/systems.cs b/src/systems.cs
index a14cd4a..ad7ebaa 100644
--- a/src/systems.cs
+++ b/src/systems.cs
@@ -164,7 +164,15 @@ public void Init () {
 
         public void Run () {
             for (int i = 0, iMax = _runSystemsCount; i < iMax; i++) {
+
+#if DEBUG && LEOECSLITE_PROFILESYSTEMS
+                UnityEngine.Profiling.Profiler.BeginSample(_runSystems[i].GetType().Name);
+#endif
                 _runSystems[i].Run (this);
+#if DEBUG && LEOECSLITE_PROFILESYSTEMS
+                UnityEngine.Profiling.Profiler.EndSample();
+#endif
+                
 #if DEBUG && !LEOECSLITE_NO_SANITIZE_CHECKS
                 var worldName = CheckForLeakedEntities ();
                 if (worldName != null) { throw new System.Exception ($"Empty entity detected in world \"{worldName}\" after {_runSystems[i].GetType ().Name}.Run()."); }
diff --git a/src/worlds.cs b/src/worlds.cs
index dfd35fb..fa4aae1 100644
--- a/src/worlds.cs
+++ b/src/worlds.cs
@@ -6,6 +6,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Reflection;
 using System.Runtime.CompilerServices;
 
 #if ENABLE_IL2CPP
@@ -256,8 +257,35 @@ public IEcsPool GetPoolById (int typeId) {
         }
 
         [MethodImpl (MethodImplOptions.AggressiveInlining)]
-        public IEcsPool GetPoolByType (Type type) {
-            return _poolHashes.TryGetValue (type, out var pool) ? pool : null;
+        public IEcsPool GetPoolByType (Type poolType) {
+            
+            if (_poolHashes.TryGetValue (poolType, out var rawPool)) {
+                return rawPool;
+            }
+
+            var genericPoolType = typeof(EcsPool<>);
+            var constructed = genericPoolType.MakeGenericType(poolType);
+
+            var poolConstructors = constructed.GetConstructors(BindingFlags.NonPublic | BindingFlags.Instance);
+            var pool = poolConstructors[0].Invoke(new object[]
+            {
+                this, _poolsCount, _poolDenseSize, Entities.Length, _poolRecycledSize
+            }) as IEcsPool;
+            
+            // var pool = Activator.CreateInstance(constructed) as IEcsPool;
+            // EcsWorld world, int id, int denseCapacity, int sparseCapacity, int recycledCapacity
+            // var pool = new EcsPool<T> (this, _poolsCount, _poolDenseSize, Entities.Length, _poolRecycledSize);
+            _poolHashes[poolType] = pool;
+            if (_poolsCount == _pools.Length) {
+                var newSize = _poolsCount << 1;
+                Array.Resize (ref _pools, newSize);
+                Array.Resize (ref _filtersByIncludedComponents, newSize);
+                Array.Resize (ref _filtersByExcludedComponents, newSize);
+            }
+            _pools[_poolsCount++] = pool;
+            return pool;
+            
+            // return _poolHashes.TryGetValue (type, out var pool) ? pool : null;
         }
 
         public int GetAllEntities (ref int[] entities) {
@@ -494,12 +522,18 @@ void Reset () {
             }
 
             [MethodImpl (MethodImplOptions.AggressiveInlining)]
-            public Mask Inc<T> () where T : struct {
-                var poolId = _world.GetPool<T> ().GetId ();
+            public Mask Inc<T> () where T : struct
+            {
+                return IncByType(typeof(T));
+            }
+            
+            [MethodImpl (MethodImplOptions.AggressiveInlining)]
+            public Mask IncByType(Type type) {
+                var poolId = _world.GetPoolByType(type).GetId ();
 #if DEBUG && !LEOECSLITE_NO_SANITIZE_CHECKS
                 if (_built) { throw new Exception ("Cant change built mask."); }
-                if (Array.IndexOf (Include, poolId, 0, IncludeCount) != -1) { throw new Exception ($"{typeof (T).Name} already in constraints list."); }
-                if (Array.IndexOf (Exclude, poolId, 0, ExcludeCount) != -1) { throw new Exception ($"{typeof (T).Name} already in constraints list."); }
+                if (Array.IndexOf (Include, poolId, 0, IncludeCount) != -1) { throw new Exception ($"{type.Name} already in constraints list."); }
+                if (Array.IndexOf (Exclude, poolId, 0, ExcludeCount) != -1) { throw new Exception ($"{type.Name} already in constraints list."); }
 #endif
                 if (IncludeCount == Include.Length) { Array.Resize (ref Include, IncludeCount << 1); }
                 Include[IncludeCount++] = poolId;
@@ -511,11 +545,19 @@ public Mask Inc<T> () where T : struct {
 #endif
             [MethodImpl (MethodImplOptions.AggressiveInlining)]
             public Mask Exc<T> () where T : struct {
-                var poolId = _world.GetPool<T> ().GetId ();
+                return ExcByType(typeof(T));
+            }
+            
+#if UNITY_2020_3_OR_NEWER
+            [UnityEngine.Scripting.Preserve]
+#endif
+            [MethodImpl (MethodImplOptions.AggressiveInlining)]
+            public Mask ExcByType(Type type) {
+                var poolId = _world.GetPoolByType(type).GetId ();
 #if DEBUG && !LEOECSLITE_NO_SANITIZE_CHECKS
                 if (_built) { throw new Exception ("Cant change built mask."); }
-                if (Array.IndexOf (Include, poolId, 0, IncludeCount) != -1) { throw new Exception ($"{typeof (T).Name} already in constraints list."); }
-                if (Array.IndexOf (Exclude, poolId, 0, ExcludeCount) != -1) { throw new Exception ($"{typeof (T).Name} already in constraints list."); }
+                if (Array.IndexOf (Include, poolId, 0, IncludeCount) != -1) { throw new Exception ($"{type.Name} already in constraints list."); }
+                if (Array.IndexOf (Exclude, poolId, 0, ExcludeCount) != -1) { throw new Exception ($"{type.Name} already in constraints list."); }
 #endif
                 if (ExcludeCount == Exclude.Length) { Array.Resize (ref Exclude, ExcludeCount << 1); }
                 Exclude[ExcludeCount++] = poolId;