Here's the hardware I used to build this project:

• 3 x Raspberry Pi 3 (Adafruit Product ID: 3055)
• Feather Huzzah! ESP8266 (Adafruit Product ID: 2821)
• Stacking Feather headers (Adafruit Product ID: 2830)
• 4400 mAh LiPo battery (Adafruit Product ID: 354)
• Half-size breadboard (Adafruit Product ID: 64)
• Jumper wires, male-male and female-male
• USB A to micro B cable for the Feather or 5v power supply with micro b connector (Adafruit Product ID: 1995)
• GA1A12S202 Log-scale Analog Light Sensor (Adafruit Product ID: 1384)

And here are the software dependencies:

• Raspbian Jessie, up to date
• Paho MQTT library (aka Mosquitto)
• Adafruit_IO library
• Python3 (because TonyD says it's 2016 and we should all use 3 :-)
• NodeMCU Lua