wtk is a proof of concept implementation from
Mark Roseman
for providing GUI functionality for Tcl in a a browser or
Javascript environment using a mechanism, which I (
apw) see similar to rpc (remote procedure call). That does not exclude the use of that package for running in the browser without any remote call.
The git repository with the sources can be found here:
wtk repository
Please correct me, if I am wrong with that statement.