libmateweather is a libgnomeweather fork. libmateweather is a library to access weather information from online services for numerous locations. libmateweather isn't supported in the devel platform, which means OS vendors won't guarantee the API/ABI long-term, but authors of open source apps should feel free to use libmateweather as users can always recompile against a new version. To use libmateweather in your code, you need to define the MATEWEATHER_I_KNOW_THIS_IS_UNSTABLE preprecessor symbol, e.g. by adding -DMATEWEATHER_I_KNOW_THIS_IS_UNSTABLE to your CFLAGS.