> Assume hostile users (security-wise).

Ah, a personal favorite of mine which often makes other people uncomfortable.

1. Users are like Marines, if it can be broken, it will be broken. If it's use is not clearly marked, it will be used incorrectly. If it can be fucked (literally or figuratively), it will be fucked.

2. Users are malicious and are actively trying to backdoor everything you do. Why? Because it's the first thing I do with a new product / what I do with the competitions products.

3. It is the developers responsibility to mitigate the above cases.