Unfortunately, I haven't encountered a single strong hacker (in terms of web). All my 3-year Rails experience was sufficient to prevent the most direct web att

Unfortunately, I haven't encountered a single strong hacker (in terms of web). All my 3-year Rails experience was sufficient to prevent the most direct web attacks: Injection, CSRF, XSS, etc. The rest is simple, keep wallet.dat securely. It's just everything the hacker wants. So, the experience isn't very applicable to other startups, I think.