I designed a programming and demo board for the ESP8266 ESP-01. Originally, I wanted a multi-purpose board usable both for connecting the ESP8266 to the PC through the FTDI cable (for easier firmware flashing), for connecting the ESP to an Arduino, and for testing code on the ESP powered by a power bank.

This is the 3rd (and latest) version of my board - it's a one-layer PCB layout:

This is the corresponding soldered PCB:

And the board with the ESP8266 plugged:

Open KiCad project (CC License) and technical details coming soon…