diff --git a/src/core/HNode.ts b/src/core/HNode.ts
index 6469300..22422aa 100644
--- a/src/core/HNode.ts
+++ b/src/core/HNode.ts
@@ -27,15 +27,22 @@ export type HProps<P extends object = any> = {
     children: unknown[];
 });
 
+export type HCallback<P extends object = any, S extends Store = Store, C extends Store = Store, T = unknown> =
+    (this: HNode<P, S, C>, props: HProps<P>, store: S, context: C) => T;
+
+export type EffectCallback<P extends object = any, S extends Store = Store, C extends Store = Store> =
+    HCallback<P, S, C, HCallback<P, S, C, void> | void>;
+
 export interface HDesc<P extends object = any, S extends Store = Store, C extends Store = Store> {
     defaultProps?: Partial<P>;
     defaultStore?: Partial<StoreType<S>>;
     storeHandlers?: PartialHandlers<StoreHandlers<S>, S>;
+    effects?: EffectCallback<P, S, C>[];
     state?: Array<keyof StoreType<S>>;
     context?: Array<keyof StoreType<C>>;
-    init?: (this: HNode<P, S, C>, props: HProps<P>, store: S, context: C) => void;
-    render: (this: HNode<P, S, C>, props: HProps<P>, store: S, context: C) => unknown;
-    clear?: (this: HNode<P, S, C>, props: HProps<P>, store: S, context: C) => void;
+    init?: HCallback<P, S, C, void>;
+    render: HCallback<P, S, C, unknown>;
+    clear?: HCallback<P, S, C, void>;
     catch?: (this: HNode<P, S, C>, err: any, props: HProps<P>, store: S, context: C) => unknown;
 }
 
@@ -52,6 +59,7 @@ export interface HNode<P extends object = EleProps, S extends Store = Store, C e
     nodes?: Node[];
     active: boolean;
     evMap?: EventMap;
+    eff?: HCallback<P, S, C, void>[];
     err?: unknown;
 }
 
diff --git a/src/core/HUI.ts b/src/core/HUI.ts
index b4fabe9..d9ac800 100644
--- a/src/core/HUI.ts
+++ b/src/core/HUI.ts
@@ -1,4 +1,4 @@
-import { HProps as _HProps, HDesc as _HDesc, HNode as _HNode } from "./HNode";
+import { HProps as _HProps, HDesc as _HDesc, HNode as _HNode, HCallback as _HCallback, EffectCallback as _EffectCallback } from "./HNode";
 import { registry, define, HType as _HType } from "./registry";
 import { _assign, _Infinity, _requestAnimationFrame } from "../utils/refCache";
 import { Store as _Store, createStore, HandlerMap as _HandlerMap, Setter as _Setter, SetterRecord as _SetterRecord, StoreType as _StoreType, StoreHandlers as _StoreHandlers, PartialHandlers as _PartialHandlers, EmptyStore as _EmptyStore } from "./Store";
@@ -43,6 +43,8 @@ HUI.cmp = compare;
 export namespace HUI {
 
     export type HProps<P extends object = any> = _HProps<P>;
+    export type HCallback<P extends object = any, S extends _Store = _Store, C extends _Store = _Store, T = unknown> = _HCallback<P, S, C, T>;
+    export type EffectCallback<P extends object = any, S extends _Store = _Store, C extends _Store = _Store> = _EffectCallback<P, S, C>;
     export type HDesc<P extends object = any, S extends _Store = _Store, C extends _Store = _Store> = _HDesc<P, S, C>;
     export type HNode<P extends object = any, S extends _Store = _Store, C extends _Store = _Store> = _HNode<P, S, C>;
 
diff --git a/src/core/initComponent.ts b/src/core/initComponent.ts
index 9aff5e9..53e1ee4 100644
--- a/src/core/initComponent.ts
+++ b/src/core/initComponent.ts
@@ -1,15 +1,16 @@
-import { HNode } from "./HNode";
+import { HNode, HCallback, HProps } from "./HNode";
 import { Store } from "./Store";
 import { supply } from "../utils/helpers";
+import { _Boolean } from "../utils/refCache";
 
-export const initComponent = function initCom(hNode: HNode<any>, store: Store) {
+export const initComponent = function initCom<P extends object = any, S extends Store = Store, C extends Store = Store>(hNode: HNode<P, S, C>, store: S) {
 
     const { props, ctx } = hNode,
         desc = hNode.desc!,
-        { defaultProps, defaultStore, storeHandlers, state, context, init } = desc;
+        { defaultProps, defaultStore, storeHandlers, state, context, init, effects } = desc;
 
     if (defaultProps) {
-        supply(props, defaultProps);
+        supply(props, defaultProps as Partial<HProps<P>>);
     }
 
     hNode.sto = store;
@@ -17,18 +18,22 @@ export const initComponent = function initCom(hNode: HNode<any>, store: Store) {
         store.setSome(defaultStore);
     }
     if (state) {
-        hNode.sto.bind(hNode, state);
+        hNode.sto.bind(hNode as unknown as HNode, state);
     }
     if (storeHandlers) {
         store.handleSome(storeHandlers);
     }
 
     if (context) {
-        ctx!.bind(hNode, context);
+        ctx!.bind(hNode as unknown as HNode, context);
     }
 
     if (init) {
         init.call(hNode, props, store, ctx!);
     }
 
+    if (effects) {
+        hNode.eff = effects.map(effect => effect.call(hNode, props, store, ctx!)).filter(_Boolean) as HCallback<P, S, C, void>[];
+    }
+
 };
\ No newline at end of file
diff --git a/src/ext/Portal.ts b/src/ext/Portal.ts
index 369dbcf..ed9712b 100644
--- a/src/ext/Portal.ts
+++ b/src/ext/Portal.ts
@@ -19,32 +19,39 @@ export interface PortalStore {
 
 export const Portal = define<PortalProps, Store<PortalStore>, EmptyStore>('HUI.Portal', {
 
-    init: function port_init(props, store) {
-        store.set('p', props.parent || _document.body);
-        store.set('f', HUI(Fragment, _null, props.children));
-    },
+    effects: [
+        function ptl_eff(props, store) {
 
-    render: function port_render(props, store, context) {
-        renderToDOM(store.get('f'), {
-            parent: store.get('p'),
-            owner: this,
-            context
-        });
-    },
+            const { parent = _document.body } = props,
+                fragment = HUI(Fragment, _null, props.children);
 
-    clear: function port_clear(props, store) {
+            store.set('p', parent);
+            store.set('f', fragment);
 
-        const fragment = store.get('f')!,
-            { ownNode, nodes } = fragment;
+            return function ptl_clr() {
 
-        clear(fragment);
+                const { ownNode, nodes } = fragment;
 
-        nodes!.forEach(node => {
-            ownNode!.removeChild(node);
-        });
+                clear(fragment);
+
+                nodes!.forEach(node => {
+                    ownNode!.removeChild(node);
+                });
+
+                nodes!.length = 0;
 
-        nodes!.length = 0;
+            };
 
+        }
+    ],
+
+
+    render: function ptl_render(props, store, context) {
+        renderToDOM(store.get('f'), {
+            parent: store.get('p'),
+            owner: this,
+            context
+        });
     }
 
 });
diff --git a/src/utils/clear.ts b/src/utils/clear.ts
index 9812469..5ddfbe8 100644
--- a/src/utils/clear.ts
+++ b/src/utils/clear.ts
@@ -11,12 +11,22 @@ export const clear = function clr(hNode: HNode<any>) {
 
     if (desc) {
 
-        if (desc.clear) {
-            try {
-                desc.clear.call(hNode, props, hNode.sto!, hNode.ctx!);
-            } catch (err) {
-                _console.error(err);
+        const { sto, ctx } = hNode;
+
+        try {
+
+            if (hNode.eff) {
+                hNode.eff.forEach(effCanceller => {
+                    effCanceller.call(hNode, props, sto!, ctx!);
+                });
             }
+
+            if (desc.clear) {
+                desc.clear.call(hNode, props, sto!, ctx!);
+            }
+
+        } catch (err) {
+            _console.error(err);
         }
 
     } else {
diff --git a/test/src/Timer.tsx b/test/src/Timer.tsx
index 0611b6e..89bf584 100644
--- a/test/src/Timer.tsx
+++ b/test/src/Timer.tsx
@@ -4,7 +4,6 @@ interface TimerProps {
 
 interface TimerStore {
     time: number;
-    timer: any;
 }
 
 type TimerStoreHandlers = {
@@ -19,17 +18,24 @@ const Timer = HUI.define<TimerProps, HUI.Store<TimerStore, TimerStoreHandlers>,
         start: 0
     },
 
+    effects: [
+        function (props, store) {
+            const timer = store.trigger('setInterval', 1000);
+            return () => {
+                clearInterval(timer);
+            };
+        }
+    ],
+
     storeHandlers: {
         setInterval(interval) {
             const timer = setInterval(this.inc, interval, 'time');
-            this.set('timer', timer);
             return timer;
         }
     },
 
     init(props, store) {
         store.set('time', props.start!);
-        store.set('timer', store.trigger('setInterval', 1000));
     },
 
     render(props, store) {
@@ -38,10 +44,6 @@ const Timer = HUI.define<TimerProps, HUI.Store<TimerStore, TimerStoreHandlers>,
                 Time: <span>{store.get('time')}</span>
             </HUI.Fragment>
         );
-    },
-
-    clear(props, store) {
-        clearInterval(store.get('timer'));
     }
 
 });
\ No newline at end of file