Here's a screenshot of a Sequentially Programmed Web App Demo):
Web-call.cc's and Mashweb's JavaScript and BiwaScheme playground. Mainly demos of Zen, a toolkit to enable sequential programming of web apps. At present there's nothing on the page that you're looking at but this README.
See also mashweb.club, github.com/Mashweb,
github.com/Mashweb/seq_webapp_biwascheme,
and github.com/tomelam.
Older websites, still useful: tomelam.blogspot.com,
tomelam.com.
Here's a screenshot of web-call.cc's homepage, listing the demos there:
Here's a screenshot of a Sequentially Programmed Web App Demo):