diff --git a/packages/omi-old/src/component.js b/packages/omi-old/src/component.js
index e63363078..fb83d76b7 100755
--- a/packages/omi-old/src/component.js
+++ b/packages/omi-old/src/component.js
@@ -44,6 +44,8 @@ export function Component(props, context) {
 
 }
 
+Component.is = 'WeElement';
+
 
 extend(Component.prototype, {
 
diff --git a/packages/omi-old/src/define.js b/packages/omi-old/src/define.js
new file mode 100644
index 000000000..be4009073
--- /dev/null
+++ b/packages/omi-old/src/define.js
@@ -0,0 +1,57 @@
+import options from '../options';
+
+const OBJECTTYPE = '[object Object]'
+const ARRAYTYPE = '[object Array]'
+
+export function define(name, ctor) {
+  if (ctor.is === 'WeElement') {
+    options.mapping[name] = ctor
+    if (ctor.data && !ctor.pure) {
+      ctor.updatePath = getUpdatePath(ctor.data)
+    }
+  }
+}
+
+export function getUpdatePath(data) {
+  const result = {}
+  dataToPath(data, result)
+  return result
+}
+
+function dataToPath(data, result) {
+  Object.keys(data).forEach(key => {
+    result[key] = true
+    const type = Object.prototype.toString.call(data[key])
+    if (type === OBJECTTYPE) {
+      _objToPath(data[key], key, result)
+    } else if (type === ARRAYTYPE) {
+      _arrayToPath(data[key], key, result)
+    }
+  })
+}
+
+function _objToPath(data, path, result) {
+  Object.keys(data).forEach(key => {
+    result[path + '.' + key] = true
+    delete result[path]
+    const type = Object.prototype.toString.call(data[key])
+    if (type === OBJECTTYPE) {
+      _objToPath(data[key], path + '.' + key, result)
+    } else if (type === ARRAYTYPE) {
+      _arrayToPath(data[key], path + '.' + key, result)
+    }
+  })
+}
+
+function _arrayToPath(data, path, result) {
+  data.forEach((item, index) => {
+    result[path + '[' + index + ']'] = true
+    delete result[path]
+    const type = Object.prototype.toString.call(item)
+    if (type === OBJECTTYPE) {
+      _objToPath(item, path + '[' + index + ']', result)
+    } else if (type === ARRAYTYPE) {
+      _arrayToPath(item, path + '[' + index + ']', result)
+    }
+  })
+}
diff --git a/packages/omi-old/src/omi.js b/packages/omi-old/src/omi.js
index 18eb52839..641b84dda 100755
--- a/packages/omi-old/src/omi.js
+++ b/packages/omi-old/src/omi.js
@@ -6,6 +6,7 @@ import { rerender } from './render-queue';
 import options from './options';
 
 const instances = [];
+const WeElement = Component
 
 options.root.Omi = {
 	h,
@@ -15,7 +16,8 @@ options.root.Omi = {
 	render,
 	rerender,
 	options,
-	instances
+	instances,
+	WeElement
 };
 
 options.root.Omi.version = '3.0.6';
@@ -28,7 +30,8 @@ export default {
 	render,
 	rerender,
 	options,
-	instances
+	instances,
+	WeElement
 };
 
 export {
@@ -39,5 +42,6 @@ export {
 	render,
 	rerender,
 	options,
-	instances
+	instances,
+	WeElement
 };
diff --git a/packages/omi-old/src/options.js b/packages/omi-old/src/options.js
index 32e4b95d9..5aef74d44 100755
--- a/packages/omi-old/src/options.js
+++ b/packages/omi-old/src/options.js
@@ -10,7 +10,7 @@ function getGlobal() {
 		return (function(){
 			return this;
 		})();
-		
+
 	}
 	return global;
 }
@@ -23,6 +23,7 @@ export default {
 
 	scopedStyle: true,
 	$store: null,
+	mapping: {},
 	isWeb: true,
 	staticStyleMapping: {},
 	doc: typeof document === 'object' ? document : null,
diff --git a/packages/omi-old/src/vdom/diff.js b/packages/omi-old/src/vdom/diff.js
index f9e29b68c..9fab7b5b2 100755
--- a/packages/omi-old/src/vdom/diff.js
+++ b/packages/omi-old/src/vdom/diff.js
@@ -69,6 +69,11 @@ function idiff(dom, vnode, context, mountAll, componentRoot) {
 	// empty values (null, undefined, booleans) render as empty Text nodes
 	if (vnode==null || typeof vnode==='boolean') vnode = '';
 
+	// If the VNode represents a Component, perform a component diff:
+	let vnodeName = vnode.nodeName;
+	if (vnodeName.is === 'WeElement') {
+		return buildComponentFromVNode(dom, vnode, context, mountAll);
+	}
 
 	// Fast case: Strings & Numbers create/update Text nodes.
 	if (typeof vnode==='string' || typeof vnode==='number') {
@@ -94,14 +99,6 @@ function idiff(dom, vnode, context, mountAll, componentRoot) {
 		return out;
 	}
 
-
-	// If the VNode represents a Component, perform a component diff:
-	let vnodeName = vnode.nodeName;
-	if (typeof vnodeName==='function') {
-		return buildComponentFromVNode(dom, vnode, context, mountAll);
-	}
-
-
 	// Tracks entering and exiting SVG namespace when descending through the tree.
 	isSvgMode = vnodeName==='svg' ? true : vnodeName==='foreignObject' ? false : isSvgMode;