Sorry, just to clarify the above steps will install and compile with the latest esp8266/arduino release rc, currently:
I just want to be totally sure this is the version I'm using. I can't see where to check that the correct version is installed. The docs say it should be possible to set
platform = https://github.com/platformio/platform-espressif8266.git#feature/stage
When I do this I get error:
IOError: [Errno 2] No such file or directory: '/home/fig/.platformio/platforms/Arduino/platform.json'
Should it be possible to set in
platform = https://github.com/esp8266/Arduino/releases/tag/2.4.0