Most people don't really need things like rolling zero-downtime updates though. If you deploy your service once per week, and it takes 5 seconds to restart, tha

Most people don't really need things like rolling zero-downtime updates though. If you deploy your service once per week, and it takes 5 seconds to restart, that's still five 9s of availability, which is more than enough for tons of applications. A single Scala+postgres service on my 7 year old quad core machine can handle 10s of thousands of HTTP requests per second, which is plenty of scalability for most applications.