While the Arduino-ESP32 side is my main focus, the ESP-IDF build ought to be very similar (demo*.ino --> main.cpp, and the header and source libs aren't in their canonical locations by default).

HT16K33 Library for Arduino This is a quick and dirty library providing a relatively easy-to-use interface for driving the Holtek HT16K33 16×8 LED driver IC. I wrote it for a project I was working on, ...