ESP32 fast bit-bang I2C library for Arduino, drop in replacement for Wire.h
The library reaches up to 3 MHz I2C clock speed. No fancy bits and bobs: no timeouts, no clock stretching, blocking only... Made for fast IMU sensor reading were an occasional missed read does not matter, but bus hangups do matter.
Tested on ESP32, might work on other ESP32 variants.
Limitation: pins 0-31 only
As of December 2023 the official arduino-esp32 Wire library has some nasty bugs. In particular, there is a 1 second timeout which hangs the bus on a bad read, and this timeout can not be lowered without changing the source code, see espressif/esp-idf#4999 and espressif/arduino-esp32#5934. So occasionally (a couple times per minute) 1000 samples are missed when you are reading a sensor at 1 kHz.