That being said, is the actual production infra archi for HN described somewhere ? Curious how simple it can afford to be.

We laugh at people piling layers and layers and artifacts on their sites, all in the hope of adding redundancy, handle "webscale" load, and avoid an outage (ironically increasing the chances that _something_ will break).

However, if a single hard drive crashing somewhere can cause your site to be down for minutes or hours, some non-tech people (managers, shareholders, customers) will wonder if the site is "professionnal" enough - and I can sympathize with them.