I don't think that you can add wildcard domains to nodester since the proxy is case-sensitive.
Another user suggest that what he could do is to make a request to the nodester api every time that a new subdomain is available for your app ( assuming that you are keeping control of it). But that depends on the use case that you have for it.
We are ok with doing that.
And I don't think that's hard to implement so you should be ok. :)
/be