diff --git a/packages/inula-reactive/index.ts b/packages/inula-reactive/index.ts
index 058b87ee..0e44a8a0 100644
--- a/packages/inula-reactive/index.ts
+++ b/packages/inula-reactive/index.ts
@@ -31,4 +31,4 @@ export {
   computed,
   isReactiveObj,
   untrack
-}
+};
diff --git a/packages/inula-reactive/src/RNode.ts b/packages/inula-reactive/src/RNode.ts
index 6bc02ac5..869e9f42 100644
--- a/packages/inula-reactive/src/RNode.ts
+++ b/packages/inula-reactive/src/RNode.ts
@@ -26,7 +26,6 @@ export type State = typeof Fresh | typeof Check | typeof Dirty;
 type NonClean = typeof Check | typeof Dirty;
 
 export interface RNodeOptions {
-  root?: Root<any> | null;
   isSignal?: boolean;
   isEffect?: boolean;
   isComputed?: boolean;
diff --git a/packages/inula-reactive/src/RNodeCreator.ts b/packages/inula-reactive/src/RNodeCreator.ts
index ea3c57bb..b8da0594 100644
--- a/packages/inula-reactive/src/RNodeCreator.ts
+++ b/packages/inula-reactive/src/RNodeCreator.ts
@@ -17,23 +17,23 @@ import { isPrimitive } from './Utils';
 import { RNode } from './RNode';
 import { ProxyRNode } from './Types';
 import { RProxyNode } from './RProxyNode';
-import {getRNodeVal, getRootRNode} from "./RNodeAccessor";
+import { getRNodeVal, getRootRNode } from './RNodeAccessor';
 
 export type Reactive<T = any> = RNode<T> | Atom<T>;
 
 export function createReactive<T extends any>(raw?: T): ReactiveProxy<T> {
   if (isPrimitive(raw) || raw === null || raw === undefined) {
-    return new RNode(raw, { isSignal: true });
+    return new RNode(raw, {isSignal: true});
   } else {
     const node = new RProxyNode(null, {
-      root: { $: raw },
+      root: {$: raw},
     });
     return node.proxy as ReactiveProxy<T>;
   }
 }
 
 export function createComputed<T>(fn: T) {
-  const rNode = new RProxyNode(fn, { isComputed: true });
+  const rNode = new RProxyNode(fn, {isComputed: true});
   return rNode.proxy;
 }
 
diff --git a/packages/inula-reactive/src/RProxyNode.ts b/packages/inula-reactive/src/RProxyNode.ts
index b1a03545..e4a2118a 100644
--- a/packages/inula-reactive/src/RProxyNode.ts
+++ b/packages/inula-reactive/src/RProxyNode.ts
@@ -25,7 +25,7 @@ export interface RNodeOptions {
   isEffect?: boolean;
   isComputed?: boolean;
   isProxy?: boolean;
-  parent?: RNode<any> | null;
+  parent?: RProxyNode<any> | null;
   key?: KEY | null;
   equals?: (a: any, b: any) => boolean;
 }
@@ -55,8 +55,10 @@ export class RProxyNode<T = any> extends RNode<T> {
     this.key = options?.key as KEY;
     this.root = options?.root || {};
 
-    if (this.parent && !this.parent.children) {
-      this.parent.children = new Map();
+    if (this.parent) {
+      if (!this.parent.children) {
+        this.parent.children = new Map();
+      }
       this.parent.children.set(this.key, this);
     }
 
@@ -109,7 +111,7 @@ export class RProxyNode<T = any> extends RNode<T> {
     return getRNodeVal(this);
   }
 
-  setValue(value: any) {
+  setValue(value: T) {
     setRNodeVal(this, value);
   }
 }
diff --git a/packages/inula-reactive/src/Utils.ts b/packages/inula-reactive/src/Utils.ts
index 07ed92bb..b2607c81 100644
--- a/packages/inula-reactive/src/Utils.ts
+++ b/packages/inula-reactive/src/Utils.ts
@@ -30,7 +30,7 @@ export function isPrimitive(obj: unknown): boolean {
   return obj != null && type !== 'object' && type !== 'function';
 }
 
-export function isFunction<T extends (...prev: any) => any>(obj: unknown): obj is T {
+export function isFunction<T extends (...prev: any) => any>(obj: unknown): obj is Function {
   return typeof obj === 'function';
 }
 
diff --git a/packages/inula-reactive/tests/reactive.test.ts b/packages/inula-reactive/tests/reactive.test.ts
index abeaefd5..de444fb7 100644
--- a/packages/inula-reactive/tests/reactive.test.ts
+++ b/packages/inula-reactive/tests/reactive.test.ts
@@ -1,31 +1,66 @@
 import { reactive, computed, watch } from '../index';
 
 describe('test reactive', () => {
-  it('two signals, one computed', () => {
+  it('computation should work with two reactive', () => {
     const a = reactive(7);
     const b = reactive(1);
     let callCount = 0;
 
-    const c = computed(() => {
+    const product = computed(() => {
       callCount++;
-      return { a: a.get() * b.get() };
+      return { value: a.get() * b.get() };
     });
 
-    watch(() => {
-      console.log(a.get());
-    });
+    // computed should be lazy
+    expect(callCount).toBe(0);
 
     expect(a.read()).toBe(7);
 
     a.set(2);
-    expect(c.a.read()).toBe(2);
+    expect(product.value.read()).toBe(2);
 
     b.set(3);
-    expect(c.a.get()).toBe(6);
+    expect(product.value.get()).toBe(6);
+    expect(callCount).toBe(2);
 
-    expect(callCount).toBe(3);
-    c.read();
-    expect(callCount).toBe(3);
+    product.read();
+    // computed function should not be invoked
+    expect(callCount).toBe(2);
+  });
+
+  it('computations should be triggered when source is same reactive', () => {
+    const pos = reactive({ x: 0, y: 0 });
+    let xCalledTimes = 0;
+    let yCalledTimes = 0;
+
+    const x = computed(() => {
+      xCalledTimes++;
+      return pos.x.get();
+    });
+
+    const y = computed(() => {
+      yCalledTimes++;
+      return pos.y.get();
+    });
+
+    expect(x.read()).toBe(0);
+    expect(y.read()).toBe(0);
+    expect(xCalledTimes).toBe(1);
+    expect(yCalledTimes).toBe(1);
+
+    // when pos.x changed, x should be triggered and y should not
+    pos.x.set(1);
+    expect(x.read()).toBe(1);
+    expect(y.read()).toBe(0);
+    expect(xCalledTimes).toBe(2);
+    expect(yCalledTimes).toBe(1);
+
+    // when pos.y changed, y should be triggered and x should not
+    pos.y.set(1);
+    expect(x.read()).toBe(1);
+    expect(y.read()).toBe(1);
+    expect(xCalledTimes).toBe(2);
+    expect(yCalledTimes).toBe(2);
   });
 
   it('reactive is a obj', () => {