establish secure connection by using openssl library
I don't think the portable code (i.e. code within /src and /include) will ever include support for TLS beyond the basics of making sure callbacks work for any handshaking that is required. TLS support should be built into wrappers.
The MBED wrapper works with MBEDTLS on a microcontroller, but I think that is too niche to be useful to anyone.
I would at some point like to complete the "WIC++" wrapper that combines WIC with C++ asio. This would add out-of-the-box TLS support among other things. There is no roadmap for when this will be ready.
If I was writing a general purpose app in C on Linux/Mac/Windows I would look to use libwebsockets. WIC is better suited to very unusual projects.
I want to write a lightweight websocket protocol implementation myself.
But since I found this project, I think it's very good and easy to integrate. There is no need to reinvent the wheel.