mtxclient is a library for the Matrix protocol used primarily in the Nheko client. This library is not a full SDK. Rather it is a thin wrapper providing functions and data structures to access the Client-Server API. Most of the semantics are described there and this library provides similarly named types and function to invoke those endpoints.
mtxclient is built on top of Boost.Asio and nlohmann/
For build instructions please refer to the README.