using an ESP8266 shield on my Arduino Uno R3 with an unofficial library I'm using the following Makefile: https://github.com/sudar/Arduino-Makefile
It works very well and I was able to get my LED to blink.

Now I bought a WiFi Shield which is NOT supported officially by the Arduino WiFi library.
It is the following one I bought: ESP8266 ESP-12E CC3000 UART WIFI Wireless Shield Board Modul für Arduino UNO R3 - you can find this on ebay: http://www.ebay.de/itm/262525969091?_trksid=p2060353.m2749.l2649&amp;ssPageName=STRK%3AMEBIDX%3AIT

What I now am about to do is to include the open source library for the ESP8266 which you can find here: https://github.com/esp8266/Arduino#documentation

Now when I try to upload my sketch it tells me that certain dependencies are not resolved. Like this one here #include &lt;functional&gt; which I was not able to include manually. My main problem here is that the github page of the ESP8266 library isn't providing enough information for me how I can get the working lib to use in my sketch.
I need to know how I can get this library to work in my sketch!
That is not a library for the Arduino. That is a core for programming the ESP8266 directly as if it were an Arduino itself.