diff --git a/packages/ecs/src/ecs.js b/packages/ecs/src/ecs.js
index 4eb392c..78cc64a 100644
--- a/packages/ecs/src/ecs.js
+++ b/packages/ecs/src/ecs.js
@@ -18,12 +18,7 @@ export default class Ecs {
 
   constructor(Components) {
     for (const i in Components) {
-      const comp = new Components[i]();
-      comp.setDirty = (entity) => {
-        comp.$$dirty = true;
-        this.dirty.add(entity);
-      };
-      this.Components[i] = comp;
+      this.Components[i] = this.trackDirtyEntities(Components[i]);
     }
   }
 
@@ -146,25 +141,24 @@ export default class Ecs {
   }
 
   destroyMany(entities) {
-    const map = {};
+    const destroying = {};
     for (let i = 0; i < entities.length; i++) {
       const entity = entities[i];
       if (!this.$$entities[entity]) {
         throw new Error(`can't destroy non-existent entity ${entity}`);
       }
       for (let j = 0; j < this.$$entities[entity].length; j++) {
-        const key = this.$$entities[entity][j];
-        if (!map[key]) {
-          map[key] = [];
+        const component = this.$$entities[entity][j];
+        if (!destroying[component]) {
+          destroying[component] = [];
         }
-        map[key].push(entity);
+        destroying[component].push(entity);
       }
       this.$$pool.push(entity);
       delete this.$$entities[entity];
-      this.dirty.delete(entity);
     }
-    for (const i in map) {
-      this.Components[i].destroyMany(map[i]);
+    for (const i in destroying) {
+      this.Components[i].destroyMany(destroying[i]);
     }
     for (let i = 0; i < this.$$systems.length; i++) {
       this.$$systems[i].deindex(entities);
@@ -189,14 +183,13 @@ export default class Ecs {
         entity = entities[i];
       }
       if (onlyDirty && !this.dirty.has(entity)) {
-        // eslint-disable-next-line no-continue
         continue;
       }
       view.setBigUint64(cursor, BigInt(entity), true);
       cursor += 8;
       const components = this.$$entities[entity];
       view.setUint16(cursor, components.length, true);
-      const componentLengthIndex = cursor;
+      const componentsWrittenIndex = cursor;
       cursor += 2;
       if (0 === components.length) {
         continue;
@@ -215,7 +208,7 @@ export default class Ecs {
         instance.serializer.encode(source, view, cursor);
         cursor += instance.schema.sizeOf(source);
       }
-      view.setUint16(componentLengthIndex, componentsWritten, true);
+      view.setUint16(componentsWrittenIndex, componentsWritten, true);
     }
   }
 
@@ -256,6 +249,13 @@ export default class Ecs {
     }
   }
 
+  setClean() {
+    for (const i in this.Components) {
+      this.Components[i].setClean();
+    }
+    this.dirty.clear();
+  }
+
   sizeOf(entities, onlyDirty) {
     let size = 0;
     if (0 === entities.length) {
@@ -294,16 +294,9 @@ export default class Ecs {
     }
   }
 
-  tickClean() {
-    for (const i in this.Components) {
-      this.Components[i].setClean();
-    }
-    this.dirty.clear();
-  }
-
   tickFinalize() {
     this.tickDestruction();
-    this.tickClean();
+    this.setClean();
   }
 
   tickDestruction() {
@@ -320,4 +313,13 @@ export default class Ecs {
     }
   }
 
+  trackDirtyEntities(Component) {
+    const component = new Component();
+    component.setDirty = (entity) => {
+      component.$$dirty = true;
+      this.dirty.add(entity);
+    };
+    return component;
+  }
+
 }