diff --git a/flow/component.js b/flow/component.js
index 04418ded..da6f9ca6 100644
--- a/flow/component.js
+++ b/flow/component.js
@@ -1,6 +1,7 @@
 import type { Config } from '../src/core/config'
 import type VNode from '../src/core/vdom/vnode'
 import type Watcher from '../src/core/observer/watcher'
+import type StringNode from '../src/server/optimizing-compiler/runtime-helpers'
 
 declare interface Component {
   // constructor information
@@ -108,6 +109,11 @@ declare interface Component {
   // resolve scoped slots
   _u: (scopedSlots: ScopedSlotsData, res?: Object) => { [key: string]: Function };
 
+  // SSR specific
+  _ssrNode: (open: string, close?: string, ) => StringNode;
+  _ssrList: (val: any, render: () => string) => string;
+  _ssrEscape: (v: string) => string;
+
   // allow dynamic method registration
   [key: string]: any
 };
diff --git a/src/compiler/codegen/index.js b/src/compiler/codegen/index.js
index c082d9dd..1ea6450c 100644
--- a/src/compiler/codegen/index.js
+++ b/src/compiler/codegen/index.js
@@ -32,7 +32,7 @@ export class CodegenState {
   }
 }
 
-type CodegenResult = {
+export type CodegenResult = {
   render: string,
   staticRenderFns: Array<string>
 };
diff --git a/src/compiler/to-function.js b/src/compiler/to-function.js
index cf13e581..6137422c 100644
--- a/src/compiler/to-function.js
+++ b/src/compiler/to-function.js
@@ -6,7 +6,6 @@ import { warn, tip } from 'core/util/debug'
 type CompiledFunctionResult = {
   render: Function;
   staticRenderFns: Array<Function>;
-  stringRenderFns?: Array<Function>;
 };
 
 function createFunction (code, errors) {
@@ -80,12 +79,6 @@ export function createCompileToFunctionFn (compile: Function): Function {
     res.staticRenderFns = compiled.staticRenderFns.map(code => {
       return createFunction(code, fnGenErrors)
     })
-    // ssr-specific
-    if (res.stringRenderFns) {
-      res.stringRenderFns = compiled.stringRenderFns.map(code => {
-        return createFunction(code, fnGenErrors)
-      })
-    }
 
     // check function generation errors.
     // this should only happen if there is a bug in the compiler itself.
diff --git a/src/server/optimizing-compiler/codegen.js b/src/server/optimizing-compiler/codegen.js
index 0c6b4d0e..c78ee650 100644
--- a/src/server/optimizing-compiler/codegen.js
+++ b/src/server/optimizing-compiler/codegen.js
@@ -16,11 +16,7 @@ import {
   CodegenState
 } from 'compiler/codegen/index'
 
-type SSRCompileResult = {
-  render: string;
-  staticRenderFns: Array<string>;
-  stringRenderFns: Array<string>;
-};
+import type { CodegenResult } from 'compiler/codegen/index'
 
 // segment types
 const RAW = 0
@@ -32,29 +28,19 @@ type StringSegment = {
   value: string;
 };
 
-class SSRCodegenState extends CodegenState {
-  stringRenderFns: Array<string>;
-
-  constructor (options: CompilerOptions) {
-    super(options)
-    this.stringRenderFns = []
-  }
-}
-
 export function generate (
   ast: ASTElement | void,
   options: CompilerOptions
-): SSRCompileResult {
-  const state = new SSRCodegenState(options)
+): CodegenResult {
+  const state = new CodegenState(options)
   const code = ast ? genSSRElement(ast, state) : '_c("div")'
   return {
     render: `with(this){return ${code}}`,
-    staticRenderFns: state.staticRenderFns,
-    stringRenderFns: state.stringRenderFns
+    staticRenderFns: state.staticRenderFns
   }
 }
 
-function genSSRElement (el: ASTElement, state: SSRCodegenState): string {
+function genSSRElement (el: ASTElement, state: CodegenState): string {
   if (el.for && !el.forProcessed) {
     return genFor(el, state, genSSRElement)
   } else if (el.if && !el.ifProcessed) {
diff --git a/src/server/optimizing-compiler/index.js b/src/server/optimizing-compiler/index.js
index dabe398f..893630d6 100644
--- a/src/server/optimizing-compiler/index.js
+++ b/src/server/optimizing-compiler/index.js
@@ -15,7 +15,6 @@ export const createCompiler = createCompilerCreator(function baseCompile (
   return {
     ast,
     render: code.render,
-    staticRenderFns: code.staticRenderFns,
-    stringRenderFns: code.stringRenderFns
+    staticRenderFns: code.staticRenderFns
   }
 })
diff --git a/src/server/optimizing-compiler/runtime-helpers.js b/src/server/optimizing-compiler/runtime-helpers.js
index d2b349b3..775b6717 100644
--- a/src/server/optimizing-compiler/runtime-helpers.js
+++ b/src/server/optimizing-compiler/runtime-helpers.js
@@ -1,15 +1,35 @@
 /* @flow */
 
+import { escape } from 'he'
 import { isObject } from 'shared/util'
 
-function StringNode (open, close, children) {
-  this.isString = true
-  this.open = open
-  this.close = close
-  this.children = children
+export function installSSRHelpers (vm: Component) {
+  let Ctor = vm.constructor
+  while (Ctor.super) {
+    Ctor = Ctor.super
+  }
+  if (!Ctor.prototype._ssrNode) {
+    Ctor.prototype._ssrNode = createStringNode
+    Ctor.prototype._ssrList = createStringList
+    Ctor.prototype._ssrEscape = escape
+  }
+}
+
+export class StringNode {
+  isString: boolean;
+  open: string;
+  close: ?string;
+  children: ?Array<any>;
+
+  constructor (open: string, close?: string, children?: Array<any>) {
+    this.isString = true
+    this.open = open
+    this.close = close
+    this.children = children
+  }
 }
 
-export function createStringNode (
+function createStringNode (
   open: string,
   close?: string,
   children?: Array<any>
@@ -17,7 +37,7 @@ export function createStringNode (
   return new StringNode(open, close, children)
 }
 
-export function createStringList (val: any, render: () => string): string {
+function createStringList (val: any, render: () => string): string {
   let ret = ''
   let i, l, keys, key
   if (Array.isArray(val) || typeof val === 'string') {
diff --git a/src/server/render.js b/src/server/render.js
index e7b46127..db10c92d 100644
--- a/src/server/render.js
+++ b/src/server/render.js
@@ -5,15 +5,11 @@ const { escape } = require('he')
 import { SSR_ATTR } from 'shared/constants'
 import { RenderContext } from './render-context'
 import { ssrCompileToFunctions } from 'web/server/compiler'
+import { installSSRHelpers } from './optimizing-compiler/runtime-helpers'
 import { createComponentInstanceForVnode } from 'core/vdom/create-component'
 
 import { isDef, isUndef, isTrue } from 'shared/util'
 
-import {
-  createStringNode,
-  createStringList
-} from './optimizing-compiler/runtime-helpers'
-
 let warned = Object.create(null)
 const warnOnce = msg => {
   if (!warned[msg]) {
@@ -23,9 +19,6 @@ const warnOnce = msg => {
 }
 
 const normalizeRender = vm => {
-  vm._ssrEscape = escape
-  vm._ssrNode = createStringNode
-  vm._ssrList = createStringList
   const { render, template } = vm.$options
   if (isUndef(render)) {
     if (template) {
@@ -310,6 +303,7 @@ export function createRenderFunction (
       isUnaryTag, modules, directives,
       cache
     })
+    installSSRHelpers(component)
     normalizeRender(component)
     renderNode(component._render(), true, context)
   }