sandboxed templates

I'm a little new to rails, but I'm quite familiar with django.

I'm trying to build an app with user uploadable page templates, is
there a production ready template engine appropriate for this? I found
ruty, but it appears to be ancient.

I'd give a go if I were you (extracted from
shopify where it has got plenty of production use)


How about Radius? The Radiant framework is good for example.