what about rust for webapps? are there any frameworks out there?

Not really. A lot of the infrastructure has kept changing for a while (eg, the IO facilities were recently rewritten), so code for older versions of Rust (like [1]) fall behind and do not get updated anymore.

With Chris Morgan's rust-http library (which I think is also used by Servo), you should have the base on which to build a web framework. Somebody apparently wrote (and still maintains) a pure Rust Postgresql driver ([2]), so you could in theory write a simple CRUD webapp, if you're willing to write the routing yourself.

1: https://github.com/erickt/mre

2: https://github.com/sfackler/rust-postgres