Hi! Just go to tiddlywiki.com and look out for the “Generating Static Sites with TiddlyWiki” tiddler for full explanation.
in very short: use the --rendertiddlers command of tiddlywiki with the list of all wanted tiddlers as subsequent arguments of the command line. The problem is, this is done in an other process than the one serving as a web server currently run.
Now, if you had the control of the server, you could launch a daemon to just do that on each new or updated file within the tiddlers directory. As for deleted and renamed tiddlers, it would require a simple rm command also launched by a similar mechanism. But of course, this is not possible for any hosting service like github. You would need an other server on your control that would just do that on a copy of the tiddlers files it would keep in sync. I would think that manually launching the update of the static site would be wiser and less energy-hungry.
Regards,