GETting Conditionally - The Bare Basics - Julik Tarkhanov

It is often that random tweets somehow get me into a frenzy – somebody is wrong on the internet, yet again. But when I gave this a second thought, I figured that… this statement has more merit than I would have wanted it to have. It has merit because we do not know the very basics of cache control that are necessary (and there are not that many)! It does not have merit in the sense that force-prefetching all of your includes through Vercel’s magic RSC-combine will not, actually, solve all your problems. They are talking in solutions that they sell, and what they are not emphasizing is that the issue is with the “developer slaps ‘Cache-Control’” part. Moreover: as I will explain, a lot of juice can be squeezed out of you by CDN providers exactly because your cache control is not in order and they offer you tools that kind of “force” your performance back into a survivable state. With some improvement for your users, and to the detriment of your wallet. But first, let’s rewind and see what those CDNs actually do.