Stay out of the way. Osmos is intuitive and largely transparent to developers, and, most of all, doesn't attempt to be “smarter” than its human masters. It can also be easily mocked away for testing without having to write specialized code. Fail early, and fail loudly. In debug mode, Osmos uses Direct Proxies to trap access to a document; if attempts are made to read or write non-existent fields, an error is immediately thrown to help you and pinpoint common mistakes before they end up in production.