> Furthermore, after looking at the WT documentation it seems horrific to construct frontends in...

The front-end is jQuery and plain CSS or Bootstrap; and if JavaScript is not available then it falls back to complete server-side rendering, else it is hybrid server-client rendering.

> maybe not so bad for APIs though.

According to the creators of Wt, though you can write APIs, it is not yet architecturally optimised for REST API development.