TI-83 ESP8266 Python module
With the help of a custom firmware, the Python module is converted into an USB to serial bridge, connected to an ESP8266 module that was added inside the case.
The ESP8266 is running a stock MicroPython. The video is showing some interactions with the ESP8266 over WiFi with MicroPython WebREPL, while the module is connected to the calculator.
Everything typed on the WebREPL could have been entered directly on the calculator, but typing on a real keyboard if far more easy (at least for me) !