Word on Hacker News is that Netflix is one of AWS' premiere showcase customers and gets discounts that we couldn't dream of.

If you have dynamic workloads, need to be HA, scalable and multi region, AWS is worth every cent.

If you are running a webapp and a database with a known workload, not so much.

Seems fine for server-side development. For client-side, please don't kill my battery.

Performance has never mattered. That's why Internet Explorer's map access implementation was exponential instead of logarithmic (to the size of the map).

That one piece of lazy coding held back Javascript on their platform for years, and I'd argue that it as the most significant cause of their browser's market share plummeting (or at last tied with lack of adblockers).