A minimalist example of Alexa-Lambda-Arduino integration. A user can invoke the Alexa skill by saying "Alexa, use little light," and verbally toggle the LED on an ESP8266 board.
alexa.json is the code of the Alexa skill, which has only one customized intent with several sample utterances and a customized binary slot.
lambda.py is the function code for AWS lambda. Remember to add the Alexa skill as the only trigger of the function.
server.ino is the code for an ESP8266 board with Arduino (Wemos D1).
References