Be kind and show some humility. No one is perfect -- especially YOU. Everyone has different personalities and your comments may be received as hurtful by the receiver, even if that is not your intention. Be mindful of how someone might interpret your comments.Do not assume the developer is ignorant of something. Instead, you should kindly ask, "Did you know about this pattern/methodology we use in Rock...", etc.It is not your role to re-test or verify the operation of the code. You should assume that the author of the code has tested it thoroughly. If you think there is a problem, however, you may want to test it before providing feedback. Trust your gut (and the Holy Spirit).It is OK to not mention something if it is a very minor issue.