Ask HN: Where can I get constructive criticism for my app/website?

...besides Show HN. In the Show HN description, it states, that releases are not worth a 'Show HN' post. This creates some pressure, because you only get one shot with the HN community, so you're product better be free of major bugs. And sometimes, you just don't know anyone personally, who will be able to provide constructive criticism, since nobody is passionate enough neither from the technical, nor 'idea' side about your project.

Is there a solution on the web where you can provide your not-so production level solution, preferably anonymously, and get constructive feedback?