As a learning experience of jester a project of mine is: <https://github.com/some-avail/json2web?tab=readme-ov-file>
But I use the web-interface only to create offline apps; but it can a learning-point. I also thought Karax could not be scraped or spidered; you dont see much html-code in the page-source. But apparently there is some way because the firefox-translation-function renders a nicely translated page...I dont know how they do it thoe. But Jester is only one webserver; there are more. Since Jester appears to be no longer maintained I am also looking for alternatives...
