I have some solid experience with the ESP32 running the Arduino core and have been using the Preferences library to store, you guessed it, preferences, to NVS on that platform. It is an easy and smooth process. https://autoclicker.me
I am trying to port my code to the 8266 running the Arduino core because I do not need most of the capabilities of the ESP32. I am having trouble finding the library though, and multiple web searches trying to figure out if the Preferences library is supposed to work have led me nowhere. As far as I can tell the 8266 does have NVS functionality (at least it has partitioning/FS support).
Anyway my build dies quickly with "fatal error: Preferences.h: No such file or directory". Tips on how to move forward from here? I believe I have solved all my other issues at this point.