But the latest revelations scare me. It's one thing to find and exploit vulnerabilities in software; there's a lot of software out there which was written by developers with very little understanding of cryptography or software security, and it shows. If you care about security, we reasoned, stick to software written by people who know what they're doing — indeed, when I talk to users of Tarsnap, my online backup service, one of the most common things I hear is "you're good at security, so we know your code will keep our data safe". That reasoning is now clearly flawed: We now have evidence that the NSA is deliberately sabotaging online security — influencing (and weakening) cryptographic standards, bribing companies to insert "back doors" into their software, and even sending developers to "accidentally" insert bugs into products. It's not enough to trust that I know what I'm doing: You have to trust that I'm not secretly working for the NSA.