HAML (and others) should be supported as template languages.

[ghost]

We leverage Tilt to support multiple template languages but we're still only providing ERB support. We should support all template languages provided by Tilt(such as HAML, Slim, …)

[wikimatze]

You mean instead of using default.html.erb we should also include default.html.haml and so on, right? I here only familiar with haml and could do some experimental stuff for this language so that future refinements are possible.

[ghost]

Yes, default.html.erb, default.html.haml, etc.