Been using BearSSL in side projects on and off, and it's an excellent little library. That said, I use MbedTLS for production work on embedded hardware because

Been using BearSSL in side projects on and off, and it's an excellent little library. That said, I use MbedTLS for production work on embedded hardware because it just integrates better with the other bits and pieces of code, and often comes as part of the platform SDK itself or has been tested with the platform. This plays a big part in getting people to use it.