The goal of the project, apparently, is to make a GUI toolkit in Go with no C/C++ dependencies whatsoever [1]. Of course going that route requires coming to grips with the fact that using a raw display environment requires implementing a lot of stuff like mapping keyboard events to actual text strings.
[1] I guess we're supposed to ignore the fact that the X11 server is a massive C application.
But you don't link against the X11 server, you communicate via sockets with it. So the client application has no direct dependency of the X server implementation. Like a web server, the X server could be written in any language.
[1] I guess we're supposed to ignore the fact that the X11 server is a massive C application.