OK, what the hell is he talking about, I hear you say.
A few months ago I bought a new wifi enabled MCU (then) called Spark Photon (https://docs.particle.io/datasheets/photon-datasheet/). It comes with its own Arduino inspired IDE and some cloud API. Which it seemed to me everything runs through, all my code, sensor readings, the lot. I'm not a fan of putting stuff on the cloud and only flashing over-the-air, so I looked for alternatives in terms of firmware. Enter VIPER (www.viperize.it), a Python based firmware for MCUs.
After connecting the Photon to the Particle cloud once (and with great difficulty, I must say), it was time to follow the VIPER guys; instructions and "viperize" the Photon. With the right DFU drivers and VIPER installed it went ahead just fine. Even the wifi connection was established near out-of-the box :)