It's a battery people are pretty well used to seeing included in a language. POSIX even mandates one for C. For repeatable simulation work you might want some

It's a battery people are pretty well used to seeing included in a language. POSIX even mandates one for C. For repeatable simulation work you might want something more robust, and hopefully everybody knows it's no use for crypto, but it's a handy thing to have around if you need to flip a digital coin.