Online Firmware Builder

Some time ago, there was a service to create specific LUA-Firmware for ESP8266 online.
Target of my project is to create something similiar for Espruino.
A first early version is running online, see a short video.

Before going next steps, I would like to get some comments/feedback/what_ever.
Available functions:

• supports PICO, EspruinoBoard, ESP8266. Others are easy to add, but there are some other items on my todo list to be solved before
  
• select a board and change default settings. For example, if you don't need crypto, uncheck it
  
• define a blacklist of jsvascript command, you will not need in your firmware version
  
• add extensions from other sources, right now they are on the server only. I'm working on extension for github.
  
• save your settings in a project on your computer for sharing or reuse with new JS_version of Espruino
  If you want to do some testing, please let me know. Actual version is still under heavy development, therefore I would like to minimize number of users until it is more stable ;-)