Python Asyncio
After 2 years of using asyncio in production, I recommend to avoid it if you can. With async programming, you take the complexity of concurrent programming, which is way harder than you can imagine.<p>Also nobody mentions this for some reason, but asyncio doesn't make your programs faster, in fact it makes everything 100x SLOWER (we measured it multiple times, compared the same thing to the sync version), but makes your program concurrent (NOT parallel), where the tradeoff is you use more CPU, maybe less memory, and can saturate your bandwidth better. Never do anything CPU-bound in an async loop!