Explicit closing tags are only needed when dealing with more complex examples, like basic conditional or loops (arrays). Rather than try to teach you on a hackernews forum, you can learn all you need to know about the syntax in 5 minutes here: https://mustache.github.io/mustache.5.html

There is even a ClojureScript implementation: https://github.com/fotoetienne/cljstache

Yes mustache, JSX and all the other templating syntax aren't pretty, but my point was that Mustache is the best I've come across so far. elegance and simplicity are in the eyes of the beholder though, so to each their own.