diff --git a/CrossPlatformModules.csproj b/CrossPlatformModules.csproj
index b262c50d3..52a85dee5 100644
--- a/CrossPlatformModules.csproj
+++ b/CrossPlatformModules.csproj
@@ -288,6 +288,10 @@
     </TypeScriptCompile>
     <TypeScriptCompile Include="es-collections.d.ts" />
     <TypeScriptCompile Include="es6-promise.d.ts" />
+    <TypeScriptCompile Include="fetch\body.ts" />
+    <TypeScriptCompile Include="fetch\fetch.ts" />
+    <TypeScriptCompile Include="fetch\headers.ts" />
+    <TypeScriptCompile Include="fetch\webidl.d.ts" />
     <TypeScriptCompile Include="file-system\file-name-resolver.d.ts" />
     <TypeScriptCompile Include="file-system\file-name-resolver.ts">
       <DependentUpon>file-name-resolver.d.ts</DependentUpon>
@@ -1670,6 +1674,8 @@
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>
     <Content Include="apps\action-bar-demo\package.json" />
+    <Content Include="fetch\package.json" />
+    <Content Include="fetch\README.md" />
     <None Include="js-libs\esprima\LICENSE.BSD" />
     <Content Include="source-control.md" />
     <Content Include="ui\segmented-bar\package.json">
diff --git a/fetch/README.md b/fetch/README.md
new file mode 100644
index 000000000..fb27fc900
--- /dev/null
+++ b/fetch/README.md
@@ -0,0 +1,17 @@
+# Isomorphic Fetch Implementation
+
+## status
+
+WIP
+
+## motivation
+
+implementation of [fetch API](https://fetch.spec.whatwg.org/) in pure javascript.
+polyfill for browser, and implemnt for node.js.
+make network http access isomorphic.
+
+
+## License
+
+The MIT License (MIT)
+Copyright (c) 2013 Jxck
diff --git a/fetch/body.ts b/fetch/body.ts
new file mode 100644
index 000000000..1070006b5
--- /dev/null
+++ b/fetch/body.ts
@@ -0,0 +1,100 @@
+// https://fetch.spec.whatwg.org/#json
+type object = JSON;
+
+type body = Object; // byte stream
+
+// https://fetch.spec.whatwg.org/#bodyinit
+type BodyInit = Blob | BufferSource | FormData | URLSearchParams | USVString
+
+// https://fetch.spec.whatwg.org/#body
+interface IBody {
+  // readonly property
+  bodyUsed:      boolean;
+
+  // method
+  arrayBuffer(): Promise<ArrayBuffer>;
+  blob():        Promise<Blob>;
+  formData():    Promise<FormData>;
+  json():        Promise<JSON>;
+  text():        Promise<USVString>;
+};
+
+// https://fetch.spec.whatwg.org/#body
+class Body implements IBody {
+  private _bodyUsed: boolean;
+  private _body:     body;
+  private _usedFlag: boolean;
+  private _mimeType: string;
+
+  get bodyUsed(): boolean {
+    return this._bodyUsed;
+  }
+
+  get body(): body {
+    return this._body;
+  }
+
+  get usedFlag(): boolean {
+    return this._usedFlag;
+  }
+
+  get mimeType(): string {
+    return this._mimeType;
+  }
+
+  consumeBody(_type: string): any {
+    // step 1
+    var p = new Promise((resolve, reject) => {
+      // step 2
+      if (this._bodyUsed == true) {
+        return reject(new TypeError("body was already used"));
+      }
+
+      // step 3
+      this._bodyUsed = true;
+
+      // step 3-1
+      var stream = this._body;
+
+      // step 3-2
+      if (stream == null) {
+        stream = [];
+      }
+
+      // step 3-3
+      // TODO: Let bytes be the result of reading from stream until it returns end-of-stream.
+      var bytes;
+
+      // step 4
+      // TODO: implement me
+      switch(_type) {
+        case "ArrayBuffer":
+        case "Blob":
+        case "FormData":
+        case "JSON":
+        case "text":
+      }
+    });
+    return p;
+  }
+
+  arrayBuffer(): Promise<ArrayBuffer> {
+    return this.consumeBody("ArrayBuffer");
+  }
+
+  blob(): Promise<Blob> {
+    return this.consumeBody("Blob");
+  }
+
+  formData(): Promise<FormData> {
+    return this.consumeBody("FormData");
+  }
+
+  json(): Promise<JSON> {
+    return this.consumeBody("JSON");
+  }
+
+  text(): Promise<USVString> {
+    return this.consumeBody("text");
+  }
+}
diff --git a/fetch/fetch.ts b/fetch/fetch.ts
new file mode 100644
index 000000000..c2dbc6f75
--- /dev/null
+++ b/fetch/fetch.ts
@@ -0,0 +1,677 @@
+/// <reference path="webidl.d.ts" />
+/// <reference path="headers.ts" />
+/// <reference path="body.ts" />
+
+// http://heycam.github.io/webidl/#common-BufferSource
+class BufferSource {
+}
+
+// https://url.spec.whatwg.org/#urlsearchparams
+class URLSearchParams {
+}
+
+// https://fetch.spec.whatwg.org/#concept-method
+enum MethodEnum {
+  OPTIONS,
+  GET,
+  HEAD,
+  POST,
+  PUT,
+  DELETE,
+  TRACE,
+  CONNECT,
+}
+
+// https://fetch.spec.whatwg.org/#simple-method
+enum SimpleMethodEnum {
+  GET,
+  HEAD,
+  POST
+}
+
+function isSimpleMethod(method: ByteString): boolean {
+  if (SimpleMethodEnum[method] !== undefined) {
+    return true;
+  }
+  return false;
+}
+
+// https://fetch.spec.whatwg.org/#forbidden-method
+enum ForbiddenMethodEnum {
+  CONNECT,
+  TRACE,
+  TRACK
+}
+
+function isForbiddenMethod(method: ByteString): boolean {
+  if (ForbiddenMethodEnum[method] !== undefined) {
+    return true;
+  }
+  return false
+}
+
+// https://fetch.spec.whatwg.org/#requestcontext
+type RequestContext = string;
+enum RequestContextEnum {
+  "audio",         "beacon",
+  "cspreport",     "download",
+  "embed",         "eventsource",
+  "favicon",       "fetch",
+  "font",          "form",
+  "frame",         "hyperlink",
+  "iframe",        "image",
+  "imageset",      "import",
+  "internal",      "location",
+  "manifest",      "object",
+  "ping",          "plugin",
+  "prefetch",      "script",
+  "serviceworker", "sharedworker",
+  "subresource",   "style",
+  "track",         "video",
+  "worker",        "xmlhttprequest",
+  "xslt"
+};
+
+// https://fetch.spec.whatwg.org/#concept-request-context-frame-type
+enum ContextFrameTypeEnum {
+  "auxiliary",
+  "top-level",
+  "nested",
+  "none"
+}
+
+// https://fetch.spec.whatwg.org/#concept-request-mode
+type RequestMode = string;
+enum RequestModeEnum {
+  "same-origin",
+  "no-cors",
+  "cors"
+};
+
+// https://fetch.spec.whatwg.org/#concept-request-credentials-mode
+type RequestCredentials = string;
+enum RequestCredentialsEnum {
+  "omit",
+  "same-origin",
+  "include"
+};
+
+// https://fetch.spec.whatwg.org/#concept-request-cache-mode
+type RequestCache = string;
+enum RequestCacheEnum {
+  "default",
+  "bypass",
+  "reload",
+  "revalidate",
+  "force-cache",
+  "offline"
+};
+
+// https://fetch.spec.whatwg.org/#concept-response-type
+type ResponseType = string;
+enum ResponseTypeEnum {
+  "basic",
+  "cors",
+  "default",
+  "error",
+  "opaque"
+};
+
+/////////////////////////////
+/// Request
+/////////////////////////////
+
+// https://fetch.spec.whatwg.org/#requestinfo
+type RequestInfo = Request | USVString;
+
+// https://fetch.spec.whatwg.org/#request
+interface IRequest extends IBody {
+  // readonly property
+  method:      ByteString;
+  url:         USVString;
+  headers:     Headers;
+  context:     RequestContext;
+  referrer:    DOMString;
+  mode:        RequestMode;
+  credentials: RequestCredentials;
+  cache:       RequestCache;
+
+  // method
+  clone():     IRequest;
+};
+
+// https://fetch.spec.whatwg.org/#requestinit
+// dictionary RequestInit
+interface RequestInit {
+  method:      ByteString;
+  headers:     HeadersInit;
+  body:        BodyInit;
+  mode:        RequestMode;
+  credentials: RequestCredentials;
+  cache:       RequestCache;
+};
+
+type Client = Object;
+type Referrer = Object;
+type Context = Object;
+
+type request = {
+  method:                string;
+  url:                   string;
+  headerList:            Header[];
+  unsafeRequestFlag:     boolean;
+  body:                  body;
+  //TODO: client:        Client;
+  context:               Context;
+  //TODO: origin:        string;
+  forceOriginHeaderFlag: boolean;
+  sameOriginDataURLFlag: boolean;
+  //TODO: referrer:      Referrer;
+  mode:                  string;
+  credentialsMode:       string;
+  cacheMode:             string;
+}
+
+class Request implements IRequest {
+  // readonly property on IRequest
+  private _method:      ByteString;
+  private _url:         USVString;
+  private _headers:     Headers;
+  private _context:     RequestContext;
+  private _referrer:    DOMString;
+  private _mode:        ByteString;
+  private _credentials: RequestCredentials;
+  private _cache:       RequestCache;
+
+  // readonly property on IBody
+  private _bodyUsed:    boolean;
+
+  // https://fetch.spec.whatwg.org/#dom-request-method
+  get method(): ByteString {
+    return this._method;
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-request-url
+  get url(): USVString {
+    return this._url;
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-request-headers
+  get headers(): Headers {
+    return this._headers;
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-request-context
+  get context(): RequestContext {
+    return this._context;
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-request-referrer
+  get referrer(): DOMString {
+    return null;
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-request-mode
+  get mode(): RequestMode {
+    return null;
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-request-credentials
+  get credentials(): RequestCredentials {
+    return this._credentials;
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-request-cache
+  get cache(): RequestCache {
+    return null;
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-body-bodyused
+  get bodyUsed(): boolean {
+    return this._bodyUsed;
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-request-clone
+  // method on IRequest
+  public clone(): IRequest {
+    return null;
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-body-arraybuffer
+  // method on IBody
+  public arrayBuffer(): Promise<ArrayBuffer> {
+    return null;
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-body-blob
+  public blob(): Promise<Blob> {
+    return null;
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-body-formdata
+  public formData(): Promise<FormData> {
+    return null;
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-body-json
+  public json(): Promise<JSON> {
+    return null;
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-body-text
+  public text(): Promise<USVString> {
+    return null;
+  }
+
+  // Request
+  public request:  request;
+  public body:     body;
+  public usedFlag: boolean;
+  public mimeType: string;
+
+  // https://fetch.spec.whatwg.org/#dom-request
+  constructor(input: RequestInfo, init?: RequestInit) {
+    // can't detect class by instanceof
+    // if (input instanceof Request) { }
+
+    var request: request;
+    // step 1
+    if (typeof input === "object" && input.body !== null) { // Request
+      // step 1-1
+      if (input.usedFlag) {
+        throw new TypeError("Request already used");
+      }
+      // step 1-2
+      input.usedFlag = true;
+
+      // step 2
+      request = input.request;
+    } else {
+      // step 2
+      // new request otherwise
+      request = {
+        url:                   null,
+        method:                MethodEnum[MethodEnum.GET],
+        headerList:            [],
+        unsafeRequestFlag:     false,
+        body:                  null,
+        //TODO: client:        entry settings object,
+        //TODO: origin:        entry settings object.origin,
+        forceOriginHeaderFlag: false,
+        sameOriginDataURLFlag: false,
+        referrer:              null,
+        context:               null,
+        mode:                  RequestModeEnum[RequestModeEnum["no-cors"]],
+        credentialsMode:       RequestCredentialsEnum[RequestCredentialsEnum.omit],
+        cacheMode:             RequestCacheEnum[RequestCacheEnum.default],
+      }
+    }
+
+    // step 3
+    request = {
+      url:                   request.url,
+      method:                request.method,
+      headerList:            request.headerList,
+      unsafeRequestFlag:     true,
+      body:                  request.body,
+      //TODO: client: entry settings object,
+      //TODO: origin: entry settings object.origin,
+      forceOriginHeaderFlag: true,
+      sameOriginDataURLFlag: true,
+      //TODO: referrer : request.client,
+      context:               'fetch',
+      mode:                  request.mode,
+      credentialsMode:       request.credentialsMode,
+      cacheMode:             request.cacheMode
+    }
+
+    // step 4, 5, 6
+    var fallbackMode: RequestMode = null;
+    var fallbackCredentials: RequestCredentials = null;
+    var fallbackCache: RequestCache = null;
+
+    //TODO:
+    function parseURL(url: string): string {
+      return url;
+    }
+    // step 7
+    if (typeof input === "string") {
+      // step 7-1
+      var parsedURL;
+
+      try {
+        parsedURL = parseURL(input);
+      } catch(err) {
+        // step 7-2
+        throw new TypeError(err);
+      }
+
+      // step 7-3
+      request.url = parsedURL;
+
+      // step 7-4, 7-5, 7-6
+      fallbackMode = RequestModeEnum[RequestModeEnum.cors];
+      fallbackCredentials = RequestCredentialsEnum[RequestCredentialsEnum.omit];
+      fallbackCache = RequestCacheEnum[RequestCacheEnum.default];
+    }
+
+    // step 8
+    var mode = init.mode? init.mode: fallbackMode;
+
+    // step 9
+    if (mode !== null) request.mode = mode;
+
+    // step 10
+    var credentials = init.credentials? init.credentials: fallbackCredentials;
+
+    // step 11
+    if (credentials !== null) request.credentialsMode = credentials;
+
+    // step 12
+    var cache = init.cache? init.cache: fallbackCache;
+
+    // step 13
+    if (cache !== null) request.cacheMode = cache;
+
+    // step 14
+    if (init.method) {
+      var method = init.method;
+
+      // step 14-1
+      if(isForbiddenMethod(method)) {
+        throw new TypeError("forbidden method " + method);
+      }
+
+      // step 14-2
+      method = method.toUpperCase();
+
+      // step 14-3
+      request.method = method;
+    }
+
+    // step 15
+    var r = this;
+    r.request = request;
+    r._headers = new Headers();
+
+    // step 16
+    var headers = r.headers;
+
+    // step 17
+    if (init.headers) {
+      headers = <Headers>init.headers;
+    }
+
+    // step 18
+    r.request.headerList = [];
+
+    // step 19
+    if (r.request.mode === "no-cors") {
+      // 19-1
+      if (!isSimpleMethod(this.request.method)) {
+        throw new TypeError("not simple method" + method);
+      }
+      // 19-2
+      r.headers.guard = "request-no-CORS";
+    }
+
+    // step 20
+    r._headers = headers;
+
+    // step 21
+    if (init.body) {
+      // step 21-1
+      var result = extract(init.body);
+
+      // step 21-2
+      r.request.body = result.stream;
+
+      // step 21-3
+      if (result.contentType !== null) {
+        var hasContentType = request.headerList.some((header) => {
+          return header.name === "Content-Type";
+        });
+
+        if (!hasContentType) {
+          r._headers.append("Content-Type", result.contentType);
+        }
+      }
+    }
+
+    // step 22
+    // FIXME implement mime type extract
+    r.mimeType = null;
+  }
+}
+
+// https://fetch.spec.whatwg.org/#concept-bodyinit-extract
+function extract(object: any): any {
+  // step 1
+  var stream = [];
+
+  // step 2
+  var contentType = null;
+
+  // step 3
+  switch(object.constructor) {
+    // Blob
+    case Blob:
+      stream = object.contents;
+
+      if (object.type) {
+        contentType = object.type;
+      }
+    case BufferSource:
+      // TODO: stream = copy(object);
+    case FormData:
+      // TODO:
+    case URLSearchParams:
+      stream = object.list.toString();
+      contentType = "application/x-www-form-urlencoded;charset=UTF-8";
+    case String: // USVString
+      // stream = encode(object);
+      contentType = "text/plain;charset=UTF-8";
+  }
+
+  // step 4
+  return { stream: stream, contentType: contentType };
+}
+
+
+
+// https://fetch.spec.whatwg.org/#response
+interface IResponse extends IBody { // Response implements Body;
+  // static Response error();
+  // static Response redirect(USVString url, optional unsigned short status = 302);
+
+  type:       ResponseType; // readonly
+  url:        USVString;    // readonly
+  status:     number;       // readonly
+  statusText: ByteString;   // readonly
+  headers:    Headers;      // readonly
+  // Response clone();
+};
+
+// https://fetch.spec.whatwg.org/#responseinit
+class ResponseInit {
+  status:     number = 200;
+  statusText: ByteString  = "OK";
+  headers:    HeadersInit;
+};
+
+class response {
+  type:              string;
+  terminationReason: string;
+  url:               string;
+  status:            number;
+  statusMessage:     string;
+  headerList:        Header[];
+  body:              Body;
+  cacheState:        string;
+  TLSState:          string;
+
+  constructor() {
+    this.type              = "default";
+    this.terminationReason = "timeout";
+    this.url               = null;
+    this.status            = 200;
+    this.statusMessage     = "OK";
+    this.headerList        = [];
+    this.body              = null;
+    this.cacheState        = "none";
+    this.TLSState          = "unauthenticated";
+  }
+}
+
+// https://fetch.spec.whatwg.org/#response
+class Response implements IResponse {
+  // implements body
+  _bodyUsed: boolean;
+
+  _type:       ResponseType; // readonly
+  _url:        USVString;    // readonly
+  _status:     number;       // readonly
+  _statusText: ByteString;   // readonly
+  _headers:    Headers;      // readonly
+
+  _response:   response;
+
+  // https://fetch.spec.whatwg.org/#dom-response
+  // [Constructor(optional BodyInit body, optional ResponseInit init), Exposed=(Window,Worker)]
+  constructor(body?: BodyInit, init?: ResponseInit) {
+    if (init !== undefined) {
+      // step 1
+      if (init.status < 200 && init.status > 599) {
+        throw new RangeError("status is not in the range 200 to 599");
+      }
+
+      // step 2
+      if (init.statusText.indexOf("\r") < 0 || init.statusText.indexOf("\n") < 0) {
+        throw new TypeError("Invalid Reason-Phrase token production");
+      }
+    }
+
+    // step 3
+    var r = this;
+    r._response = new response();
+    r._headers = new Headers();
+
+    if (init !== undefined) {
+      // step 4
+      r._response.status = init.status;
+      // step 5
+      r._response.statusMessage = init.statusText;
+    }
+
+    // step 6
+    if (init.headers) {
+      // step 6-1
+      r._response.headerList = [];
+
+      // step 6-2
+      // TODO: implements fill
+      // r._response.headerList =;
+    }
+
+    // step 7
+    if (body) {
+      // step 7-1
+      var extracted = extract(body);
+      var stream = extracted.stream;
+      var contentType = extracted.contentType;
+
+      // step 7-2
+      r._response.body = stream;
+
+      // step 7-3
+      if (contentType !== null) {
+        var hasContentType = r._response.headerList.some((header) => {
+          return header.name === "Content-Type";
+        });
+
+        if (!hasContentType) {
+          // TODO: append
+          // r._response.headerList.append(Header("Content-Type", contentType));
+        }
+      }
+
+      // step 8
+      // TODO: extracting MIME type
+
+      // step 9
+      // TODO: TLS state
+
+      // step 10
+      return r;
+    }
+  }
+
+  get bodyUsed(): boolean {
+    return this._bodyUsed;
+  }
+
+  get type(): ResponseType {
+    return this._type;
+  }
+
+  get url(): USVString {
+    return this._url;
+  }
+
+  get status(): number {
+    return this._status;
+  }
+
+  get statusText(): ByteString {
+    return this._statusText;
+  }
+
+  get headers(): Headers {
+    return this._headers;
+  }
+
+  arrayBuffer(): Promise<ArrayBuffer> {
+    return null;
+  }
+
+  blob(): Promise<Blob> {
+    return null;
+  }
+
+  formData(): Promise<FormData> {
+    return null;
+  }
+
+  json(): Promise<JSON> {
+    return null;
+  }
+
+  text(): Promise<USVString> {
+    return null;
+  }
+}
+
+
+// https://fetch.spec.whatwg.org/#globalfetch
+// Window implements GlobalFetch;
+interface Window {
+  fetch(input: RequestInfo, init?: RequestInit): Promise<IResponse>;
+};
+
+// WorkerGlobalScope implements GlobalFetch;
+this.fetch = function(input: RequestInfo, init?: RequestInit): Promise<IResponse> {
+  // step 1
+  var p = new Promise<IResponse>((resolve, reject) => {
+    try {
+      // step 2
+      var r = (new Request(input, init)).request;
+    } catch(e) {
+      reject(e);
+    }
+  });
+
+  // step 4
+  return p
+}
+
+// WorkerGlobalScope implements GlobalFetch;
diff --git a/fetch/headers.ts b/fetch/headers.ts
new file mode 100644
index 000000000..33e3d2bf6
--- /dev/null
+++ b/fetch/headers.ts
@@ -0,0 +1,341 @@
+/// <reference path="webidl.d.ts" />
+
+// https://fetch.spec.whatwg.org/#forbidden-header-name
+var ForbiddenHeaderName = {
+  "Accept-Charset":     "Accept-Charset",
+  "Accept-Encoding":    "Accept-Encoding",
+  "Access-Control-Request-Headers":  "Access-Control-Request-Headers",
+  "Access-Control-Request-Method":   "Access-Control-Request-Method",
+  "Connection":         "Connection",
+  "Content-Length":     "Content-Length",
+  "Cookie":             "Cookie",
+  "Cookie2":            "Cookie2",
+  "Date":               "Date",
+  "DNT":                "DNT",
+  "Expect":             "Expect",
+  "Host":               "Host",
+  "Keep-Alive":         "Keep-Alive",
+  "Origin":             "Origin",
+  "Referer":            "Referer",
+  "TE":                 "TE",
+  "Trailer":            "Trailer",
+  "Transfer-Encoding":  "Transfer-Encoding",
+  "Upgrade":            "Upgrade",
+  "User-Agent":         "User-Agent",
+  "Via":                "Via"
+};
+function isForbiddenHeaderName(name: ByteString): boolean {
+  if (ForbiddenHeaderName[name] !== undefined) {
+    return true;
+  }
+  var reg = /^(Proxy\-|Sec\-)/
+  if (reg.exec(name)) {
+    return true;
+  }
+
+  return false;
+}
+
+// https://fetch.spec.whatwg.org/#forbidden-response-header-name
+var ForbiddenResponseHeaderName = {
+  "Set-Cookie": "Set-Cookie",
+  "Set-Cookie2": "Set-Cookie2"
+}
+function isForbiddenResponseHeaderName(name: ByteString): boolean {
+  return ForbiddenResponseHeaderName[name] !== undefined;
+}
+
+// https://fetch.spec.whatwg.org/#simple-header
+var SimpleHeaderName = {
+  "Accept":           "Accept",
+  "Accept-Language":  "Accept-Language",
+  "Content-Language": "Content-Language"
+}
+var SimpleHeaderValue = {
+  "application/x-www-form-urlencoded": "application/x-www-form-urlencoded",
+  "multipart/form-data":               "multipart/form-data",
+  "text/plain":                        "text/plain"
+}
+function isSimpleHeader(name, value: ByteString): boolean {
+  if (SimpleHeaderName[name] !== undefined) {
+    return true;
+  }
+
+  if (name === "Content-Type") {
+    // TODO: parse value https://fetch.spec.whatwg.org/#concept-header-parse
+    if (SimpleHeaderValue[value] !== undefined) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+// https://fetch.spec.whatwg.org/#headersinit
+// typedef (Headers or sequence<sequence<ByteString>> or OpenEndedDictionary<ByteString>) HeadersInit;
+type HeadersInit = Headers | ByteString[][] | OpenEndedDictionary;
+
+// https://fetch.spec.whatwg.org/#headers
+interface IHeaders {
+  append(name, value: ByteString): void;
+  delete(name: ByteString):        void;
+  get(name: ByteString):           ByteString;
+  getAll(name: ByteString):        ByteString[];
+  has(name: ByteString):           boolean;
+  set(name, value: ByteString):    void;
+  // iterable<ByteString, ByteString>;
+};
+
+// https://fetch.spec.whatwg.org/#concept-header
+class Header {
+  name:  ByteString;
+  value: ByteString;
+  constructor(name, value: ByteString) {
+    // TODO: validation
+    this.name  = name;
+    this.value = value;
+  }
+}
+
+var Guard = {
+  "immutable":       "immutable",
+  "request":         "request",
+  "request-no-CORS": "request-no-CORS",
+  "response":        "response",
+  "none":            "none",
+}
+
+function copy<T>(obj: T): T {
+  return JSON.parse(JSON.stringify(obj));
+}
+
+// https://fetch.spec.whatwg.org/#headers
+class Headers implements IHeaders{
+  public headerList: Header[] = [];
+  public guard: string = Guard.none;
+
+  // https://fetch.spec.whatwg.org/#dom-headers
+  constructor(init?: HeadersInit) {
+    // step 1
+    var headers = this; // new Headers object
+
+    // step 2
+    if (init !== undefined) {
+      this.fill(headers, init);
+    }
+
+    // step 3
+    return headers;
+  }
+
+  // https://fetch.spec.whatwg.org/#concept-headers-fill
+  private fill(headers: Headers, object: HeadersInit) {
+    // step 1 Headers
+    if (object instanceof Headers) {
+      var headerListCopy: Header[] = copy(object.headerList);
+      headerListCopy.forEach((header: Header) => {
+        headers.append(header.name, header.value);
+      });
+      return;
+    }
+
+    // step 2 ByteString[][]
+    if (Array.isArray(object)) {
+      var headerSequence = <ByteString[][]> object;
+      headerSequence.forEach((header) => {
+        if(header.length !== 2) {
+          throw new TypeError("init for Headers was incorrect BytesString Sequence");
+        }
+        headers.append(header[0], header[1]);
+      });
+      return;
+    }
+
+    // step 3 OpenEndedDictionary
+    if (typeof object === "object") {
+      Object.keys(object).forEach((key) => {
+        headers.append(key.toString(), object[key]);
+      });
+    }
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-headers-append
+  append(name, value: ByteString): void {
+    // https://fetch.spec.whatwg.org/#concept-headers-append
+    // step 1
+    if (!name || !value) {
+      // TODO name/value validation
+      throw new TypeError("invalid name/value");
+    }
+
+    // step 2, 3, 4, 5
+    switch(this.guard) {
+      case Guard.immutable:
+        throw new TypeError("operation to immutable headers");
+      case Guard.request:
+        if (isForbiddenHeaderName(name)) {
+          return;
+        }
+      case Guard["request-no-CORS"]:
+        if (!isSimpleHeader(name, value)) {
+          return;
+        }
+      case Guard.response:
+        if (isForbiddenResponseHeaderName(name)) {
+          return;
+        }
+    }
+
+    // step 6
+    name = name.toLowerCase();
+    this.headerList.push(new Header(name, value));
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-headers-delete
+  delete(name: ByteString): void {
+    // step 1
+    if (!name) {
+      throw new TypeError("invalid name");
+    }
+
+    // step 2, 3, 4, 5
+    switch(this.guard) {
+      case Guard.immutable:
+        throw new TypeError("operation to immutable headers");
+      case Guard.request:
+        if (isForbiddenHeaderName(name)) {
+          return;
+        }
+      case Guard["request-no-CORS"]:
+        if (!isSimpleHeader(name, "invalid")) {
+          return;
+        }
+      case Guard.response:
+        if (isForbiddenResponseHeaderName(name)) {
+          return;
+        }
+    }
+
+    name = name.toLowerCase();
+    // step 6
+    this.headerList = this.headerList.filter((header: Header) => {
+      return header.name !== name;
+    });
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-headers-get
+  get(name: ByteString) :ByteString {
+    // step 1
+    if (!name) {
+      throw new TypeError("invalid name");
+    }
+
+    // step 2
+    var value: ByteString = null;
+    this.headerList.forEach((header: Header) => {
+      if (header.name === name) {
+        value = header.value;
+        return;
+      }
+    });
+
+    return value;
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-headers-getall
+  getAll(name: ByteString) :ByteString[] {
+    // step 1
+    if (!name) {
+      throw new TypeError("invalid name");
+    }
+
+    // step 2
+    var result: ByteString[] = this.headerList.reduce((acc: ByteString[], header: Header) => {
+      if (header.name === name) {
+        acc.push(header.value);
+      }
+      return acc;
+    }, []);
+
+    return result;
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-headers-has
+  has(name: ByteString) :boolean {
+    // step 1
+    if (!name) {
+      throw new TypeError("invalid name");
+    }
+
+    // step 2
+    return this.headerList.some((header: Header) => {
+      return header.name === name;
+    });
+  }
+
+  // https://fetch.spec.whatwg.org/#dom-headers-set
+  set(name, value: ByteString): void {
+    // step 1
+    if (!name || !value) {
+      throw new TypeError("invalid name/value");
+    }
+
+    switch(this.guard) {
+      // step 2
+      case Guard.immutable:
+        throw new TypeError("operation to immutable headers");
+      // step 3
+      case Guard.request:
+        if (isForbiddenHeaderName(name)) {
+          return;
+        }
+      // step 4
+      case Guard["request-no-CORS"]:
+        if (!isSimpleHeader(name, "invalid")) {
+          return;
+        }
+      // step 5
+      case Guard.response:
+        if (isForbiddenResponseHeaderName(name)) {
+          return;
+        }
+    }
+
+    // step 6
+    // see https://fetch.spec.whatwg.org/#concept-header-list-set
+
+    // step 6-1
+    name = name.toLowerCase();
+
+    // find the all indexes of headers whos key is supplyed key
+    var indexes: number[] = this.headerList.reduce((acc: number[], header: Header, index: number) => {
+      if (header.name === name) {
+        acc.push(index);
+      }
+      return acc;
+    }, []);
+
+    // count of existing headers
+    var len = indexes.length;
+
+    // step 6-3
+    // if there are no key
+    if (len === 0) {
+      // append to last and return
+      return this.append(name, value);
+    }
+
+    // step 6-2
+    // remove the headers in indexes from the last(because splice chenges index)
+    // and change first header value
+    indexes.reverse().forEach((e, i: number) => {
+      if(i === len - 1) {
+        // only replace first entry
+        this.headerList[e].value = value;
+      } else {
+        // remove duplicate from last
+        this.headerList.splice(e, 1);
+      }
+    });
+  }
+}
diff --git a/fetch/package.json b/fetch/package.json
new file mode 100644
index 000000000..f19e3419b
--- /dev/null
+++ b/fetch/package.json
@@ -0,0 +1,28 @@
+{
+  "name": "fetch-standard",
+  "author": "Jxck",
+  "license": "MIT",
+  "version": "0.0.0",
+  "description": "implementaion of https://fetch.spec.whatwg.org/",
+  "homepage": "https://github.com/Jxck/fetch",
+  "bugs": {
+    "url": "https://github.com/Jxck/fetch/issues"
+  },
+  "keywords": [
+    "fetch",
+    "whatwg"
+  ],
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/Jxck/fetch"
+  },
+  "main": "fetch.ts",
+  "scripts": {
+    "clean": "rm *.js",
+    "build": "tsc fetch.ts --target ES5",
+    "test": "npm run build && node fetch.js"
+  },
+  "devDependencies": {
+    "typescript": "^1.4.1"
+  }
+}
diff --git a/fetch/webidl.d.ts b/fetch/webidl.d.ts
new file mode 100644
index 000000000..62bae8bca
--- /dev/null
+++ b/fetch/webidl.d.ts
@@ -0,0 +1,14 @@
+// http://heycam.github.io/webidl/#idl-ByteString
+declare type ByteString = string;
+
+// http://heycam.github.io/webidl/#idl-USVString
+declare type USVString = string;
+
+// http://heycam.github.io/webidl/#idl-DOMString
+declare type DOMString = string;
+
+// see: https://fetch.spec.whatwg.org/#headersinit
+declare type OpenEndedDictionary = Object;
+
+declare class FormData { }
+declare class Blob { }
\ No newline at end of file