These are notes and short how-to's that I reference all the time. Maybe they are useful for someone else too!
How I wire a button with either 2 or 4 pins with ESP32 boards. (This works with an ESP8266 too.)
How I wire a rotary encoder with an ESP8266 and basic code to read the rotation angle and the button press.
A collection of math and geometry functions that I use all the time when coding 2D prototypes in HTML canvas, 3D models in Blender, or LEDs in C for Arduino. ...