diff --git a/src/builtin/tags/index.ts b/src/builtin/tags/index.ts
index 9c9c0df52d..924f62f832 100644
--- a/src/builtin/tags/index.ts
+++ b/src/builtin/tags/index.ts
@@ -4,6 +4,7 @@ import capture from './capture'
 import Case from './case'
 import comment from './comment'
 import include from './include'
+import render from './render'
 import decrement from './decrement'
 import cycle from './cycle'
 import If from './if'
@@ -18,7 +19,7 @@ import Continue from './continue'
 import { ITagImplOptions } from '../../template/tag/itag-impl-options'
 
 const tags: { [key: string]: ITagImplOptions } = {
-  assign, 'for': For, capture, 'case': Case, comment, include, decrement, increment, cycle, 'if': If, layout, block, raw, tablerow, unless, 'break': Break, 'continue': Continue
+  assign, 'for': For, capture, 'case': Case, comment, include, render, decrement, increment, cycle, 'if': If, layout, block, raw, tablerow, unless, 'break': Break, 'continue': Continue
 }
 
 export default tags
diff --git a/src/builtin/tags/raw.ts b/src/builtin/tags/raw.ts
index 5e2aa76b7f..791dfbe2e5 100644
--- a/src/builtin/tags/raw.ts
+++ b/src/builtin/tags/raw.ts
@@ -1,4 +1,4 @@
-import { Hash, Emitter, TagToken, Token, ITagImplOptions, Context } from '../../types'
+import { TagToken, Token, ITagImplOptions } from '../../types'
 
 export default {
   parse: function (tagToken: TagToken, remainTokens: Token[]) {
@@ -15,7 +15,7 @@ export default {
       })
     stream.start()
   },
-  render: function (ctx: Context, hash: Hash, emitter: Emitter) {
-    emitter.write(this.tokens.map((token: Token) => token.raw).join(''))
+  render: function () {
+    return this.tokens.map((token: Token) => token.raw).join('')
   }
 } as ITagImplOptions
diff --git a/src/builtin/tags/render.ts b/src/builtin/tags/render.ts
new file mode 100644
index 0000000000..b41fc75fa3
--- /dev/null
+++ b/src/builtin/tags/render.ts
@@ -0,0 +1,50 @@
+import { assert } from '../../util/assert'
+import { Expression, Hash, Emitter, TagToken, Context, ITagImplOptions } from '../../types'
+import { value, quotedLine } from '../../parser/lexical'
+import BlockMode from '../../context/block-mode'
+
+const staticFileRE = /[^\s,]+/
+const withRE = new RegExp(`with\\s+(${value.source})`)
+
+export default {
+  parse: function (token: TagToken) {
+    let match = staticFileRE.exec(token.args)
+    if (match) this.staticValue = match[0]
+
+    match = value.exec(token.args)
+    if (match) this.value = match[0]
+
+    match = withRE.exec(token.args)
+    if (match) this.with = match[1]
+  },
+  render: function * (ctx: Context, hash: Hash, emitter: Emitter) {
+    let filepath
+    if (ctx.opts.dynamicPartials) {
+      if (quotedLine.exec(this.value)) {
+        const template = this.value.slice(1, -1)
+        filepath = yield this.liquid._parseAndRender(template, ctx.getAll(), ctx.opts, ctx.sync)
+      } else {
+        filepath = yield new Expression(this.value).value(ctx)
+      }
+    } else {
+      filepath = this.staticValue
+    }
+    assert(filepath, `cannot render with empty filename`)
+
+    const originBlocks = ctx.getRegister('blocks')
+    const originBlockMode = ctx.getRegister('blockMode')
+
+    const childCtx = new Context({}, ctx.opts, ctx.sync)
+    childCtx.setRegister('blocks', {})
+    childCtx.setRegister('blockMode', BlockMode.OUTPUT)
+    if (this.with) {
+      hash[filepath] = yield new Expression(this.with).evaluate(ctx)
+    }
+    childCtx.push(hash)
+    const templates = yield this.liquid._parseFile(filepath, childCtx.opts, childCtx.sync)
+    yield this.liquid.renderer.renderTemplates(templates, childCtx, emitter)
+
+    childCtx.setRegister('blocks', originBlocks)
+    childCtx.setRegister('blockMode', originBlockMode)
+  }
+} as ITagImplOptions
diff --git a/src/context/context.ts b/src/context/context.ts
index dddbb996ea..af43ec3a57 100644
--- a/src/context/context.ts
+++ b/src/context/context.ts
@@ -11,10 +11,10 @@ export class Context {
   public environments: Scope
   public sync: boolean
   public opts: NormalizedFullOptions
-  public constructor (ctx: object = {}, opts?: NormalizedFullOptions, sync = false) {
+  public constructor (env: object = {}, opts?: NormalizedFullOptions, sync = false) {
     this.sync = sync
     this.opts = applyDefault(opts)
-    this.environments = ctx
+    this.environments = env
   }
   public getRegister (key: string, defaultValue = {}) {
     return (this.registers[key] = this.registers[key] || defaultValue)
diff --git a/src/liquid.ts b/src/liquid.ts
index f3c19bb883..2b61cafa7d 100644
--- a/src/liquid.ts
+++ b/src/liquid.ts
@@ -16,8 +16,6 @@ import { FilterImplOptions } from './template/filter/filter-impl-options'
 import IFS from './fs/ifs'
 import { toThenable, toValue } from './util/async'
 
-type nullableTemplates = ITemplate[] | null
-
 export * from './types'
 
 export class Liquid {
diff --git a/src/util/async.ts b/src/util/async.ts
index 8f8b647416..01a442316b 100644
--- a/src/util/async.ts
+++ b/src/util/async.ts
@@ -34,7 +34,7 @@ function isCustomIterable (val: any): val is IterableIterator<any> {
   return val && isFunction(val.next) && isFunction(val.throw) && isFunction(val.return)
 }
 
-export function toThenable (val: IterableIterator<any> | Thenable): Thenable {
+export function toThenable (val: IterableIterator<any> | Thenable | any): Thenable {
   if (isThenable(val)) return val
   if (isCustomIterable(val)) return reduce()
   return mkResolve(val)
@@ -61,7 +61,7 @@ export function toThenable (val: IterableIterator<any> | Thenable): Thenable {
   }
 }
 
-export function toValue (val: IterableIterator<any> | Thenable) {
+export function toValue (val: IterableIterator<any> | Thenable | any) {
   let ret: any
   toThenable(val)
     .then((x: any) => {
diff --git a/test/integration/builtin/tags/render.ts b/test/integration/builtin/tags/render.ts
new file mode 100644
index 0000000000..73f5340669
--- /dev/null
+++ b/test/integration/builtin/tags/render.ts
@@ -0,0 +1,210 @@
+import { Liquid, Drop } from '../../../../src/liquid'
+import { expect } from 'chai'
+import { mock, restore } from '../../../stub/mockfs'
+
+describe('tags/render', function () {
+  let liquid: Liquid
+  before(function () {
+    liquid = new Liquid({
+      root: '/',
+      extname: '.html'
+    })
+  })
+  afterEach(restore)
+  it('should support render', async function () {
+    mock({
+      '/current.html': 'bar{% render "bar/foo.html" %}bar',
+      '/bar/foo.html': 'foo'
+    })
+    const html = await liquid.renderFile('/current.html')
+    return expect(html).to.equal('barfoobar')
+  })
+  it('should support template string', async function () {
+    mock({
+      '/current.html': 'bar{% render "bar/{{name}}" %}bar',
+      '/bar/foo.html': 'foo'
+    })
+    const html = await liquid.renderFile('/current.html', { name: 'foo.html' })
+    return expect(html).to.equal('barfoobar')
+  })
+
+  it('should throw when not specified', function () {
+    mock({
+      '/parent.html': '{%render%}'
+    })
+    return liquid.renderFile('/parent.html').catch(function (e) {
+      console.log(e)
+      expect(e.name).to.equal('RenderError')
+      expect(e.message).to.match(/cannot render with empty filename/)
+    })
+  })
+
+  it('should throw when not exist', function () {
+    mock({
+      '/parent.html': '{%render not-exist%}'
+    })
+    return liquid.renderFile('/parent.html').catch(function (e) {
+      expect(e.name).to.equal('RenderError')
+      expect(e.message).to.match(/cannot render with empty filename/)
+    })
+  })
+
+  it('should support render with relative path', async function () {
+    mock({
+      '/bar/foo.html': 'foo',
+      '/foo/relative.html': 'bar{% render "../bar/foo.html" %}bar'
+    })
+    const html = await liquid.renderFile('foo/relative.html')
+    return expect(html).to.equal('barfoobar')
+  })
+
+  it('should support render: hash list', async function () {
+    mock({
+      '/hash.html': '{% assign name="harttle" %}{% render "user.html", role: "admin", alias: name %}',
+      '/user.html': '{{role}} : {{alias}}'
+    })
+    const html = await liquid.renderFile('hash.html')
+    return expect(html).to.equal('admin : harttle')
+  })
+
+  it('should not bleed into child template', async function () {
+    mock({
+      '/hash.html': '{% assign name="harttle" %}InParent: {{name}} {% render "user.html" %}',
+      '/user.html': 'InChild: {{name}}'
+    })
+    const html = await liquid.renderFile('hash.html')
+    return expect(html).to.equal('InParent: harttle InChild: ')
+  })
+
+  it('should support render: with', async function () {
+    mock({
+      '/with.html': '{% render "color" with "red", shape: "rect" %}',
+      '/color.html': 'color:{{color}}, shape:{{shape}}'
+    })
+    const html = await liquid.renderFile('with.html')
+    return expect(html).to.equal('color:red, shape:rect')
+  })
+  it('should support render: with as Drop', async function () {
+    class ColorDrop extends Drop {
+      public valueOf (): string {
+        return 'red!'
+      }
+    }
+    mock({
+      '/with.html': '{% render "color" with color %}',
+      '/color.html': 'color:{{color}}'
+    })
+    const html = await liquid.renderFile('with.html', { color: new ColorDrop() })
+    expect(html).to.equal('color:red!')
+  })
+  it('should support render: with passed as Drop', async function () {
+    class ColorDrop extends Drop {
+      public valueOf (): string {
+        return 'red!'
+      }
+    }
+    liquid.registerFilter('name', x => x.constructor.name)
+    mock({
+      '/with.html': '{% render "color" with color %}',
+      '/color.html': '{{color | name}}'
+    })
+    const html = await liquid.renderFile('with.html', { color: new ColorDrop() })
+    expect(html).to.equal('ColorDrop')
+  })
+
+  it('should support nested renders', async function () {
+    mock({
+      '/personInfo.html': 'This is a person {% render "card.html", person: person%}',
+      '/card.html': '<p>{{person.firstName}} {{person.lastName}}<br/>{% render "address", address: person.address %}</p>',
+      '/address.html': 'City: {{address.city}}'
+    })
+    const ctx = {
+      person: {
+        firstName: 'Joe',
+        lastName: 'Shmoe',
+        address: {
+          city: 'Dallas'
+        }
+      }
+    }
+    const html = await liquid.renderFile('personInfo.html', ctx)
+    return expect(html).to.equal('This is a person <p>Joe Shmoe<br/>City: Dallas</p>')
+  })
+
+  describe('static partial', function () {
+    it('should support filename with extention', async function () {
+      mock({
+        '/parent.html': 'X{% render child.html color:"red" %}Y',
+        '/child.html': 'child with {{color}}'
+      })
+      const staticLiquid = new Liquid({ dynamicPartials: false, root: '/' })
+      const html = await staticLiquid.renderFile('parent.html')
+      return expect(html).to.equal('Xchild with redY')
+    })
+
+    it('should support parent paths', async function () {
+      mock({
+        '/parent.html': 'X{% render bar/./../foo/child.html %}Y',
+        '/foo/child.html': 'child'
+      })
+      const staticLiquid = new Liquid({ dynamicPartials: false, root: '/' })
+      const html = await staticLiquid.renderFile('parent.html')
+      return expect(html).to.equal('XchildY')
+    })
+
+    it('should support subpaths', async function () {
+      mock({
+        '/parent.html': 'X{% render foo/child.html %}Y',
+        '/foo/child.html': 'child'
+      })
+      const staticLiquid = new Liquid({ dynamicPartials: false, root: '/' })
+      const html = await staticLiquid.renderFile('parent.html')
+      return expect(html).to.equal('XchildY')
+    })
+
+    it('should support comma separated arguments', async function () {
+      mock({
+        '/parent.html': 'X{% render child.html, color:"red" %}Y',
+        '/child.html': 'child with {{color}}'
+      })
+      const staticLiquid = new Liquid({ dynamicPartials: false, root: '/' })
+      const html = await staticLiquid.renderFile('parent.html')
+      return expect(html).to.equal('Xchild with redY')
+    })
+  })
+  describe('sync support', function () {
+    it('should support quoted string', function () {
+      mock({
+        '/current.html': 'bar{% render "bar/foo.html" %}bar',
+        '/bar/foo.html': 'foo'
+      })
+      const html = liquid.renderFileSync('/current.html')
+      return expect(html).to.equal('barfoobar')
+    })
+    it('should support template string', function () {
+      mock({
+        '/current.html': 'bar{% render name" %}bar',
+        '/bar/foo.html': 'foo'
+      })
+      const html = liquid.renderFileSync('/current.html', { name: '/bar/foo.html' })
+      return expect(html).to.equal('barfoobar')
+    })
+    it('should support render: with', function () {
+      mock({
+        '/with.html': '{% render "color" with "red", shape: "rect" %}',
+        '/color.html': 'color:{{color}}, shape:{{shape}}'
+      })
+      const html = liquid.renderFileSync('with.html')
+      return expect(html).to.equal('color:red, shape:rect')
+    })
+    it('should support filename with extention', function () {
+      mock({
+        '/parent.html': 'X{% render child.html color:"red" %}Y',
+        '/child.html': 'child with {{color}}'
+      })
+      const staticLiquid = new Liquid({ dynamicPartials: false, root: '/' })
+      const html = staticLiquid.renderFileSync('parent.html')
+      return expect(html).to.equal('Xchild with redY')
+    })
+  })
+})