Serverless, to me, is purely about efficiency. One way to measure that is the time for a "cold start" or "going from a state where you pay no money to one where

Serverless, to me, is purely about efficiency. One way to measure that is the time for a "cold start" or "going from a state where you pay no money to one where you pay money". These gains in efficiency remove the need for over-provisioning and in many cases allow you to pass these savings onto the consumer (if you want to). Heroku is a few seconds: > It only takes a few seconds to start a one-off dyno process or to scale up a web or worker process. Lambda created Firecracker to be snappier: > The duration of a cold start varies from under 100 ms to over 1 second. I think App Engine is in the same ballpark as Lambda (and predated it). Fly.io uses Firecracker too: > While Fly Machine cold starts are extremely fast, it still takes a few hundred milliseconds, so it’s still worth weighing the impact it has on performance. but WASM is yet an order of magnitude faster and cheaper: > Cloudflare Workers has eliminated cold starts entirely, meaning they need zero spin up time. This is the case in every location in Cloudflare's global network. WASM is currently limited in what it can do, but if all you're doing is manipulating and serving HTML, it's fantastic at that.