[getcrunk]

You should pick a hypothetical target first. So you got the Tshirt store but I'd pick something more complex. And then go through all layers from the start and make your app modular and take advantage of 3rd party. For example for the Tshirt store. Use a cdn. All your pages should be ssr or issr if not ssg from the getgo. This reduces your server load. And off loads the brunt of your demand onto a 3rd party. (cloud flare, CloudFront)

Then use an auth provider and payment processor. (firebase, PayPal) with dbaas.

All that's left is glue and server less functions. And none of the scaling is something you have to do.

Once you get that then sure, peice by piece you can put it on your own hardware and think it through from there (cdn, db)

[star_juice]

The heavy usage of 3rd party tools does sound about right wrt what I've heard get used to vastly expand apps after they've got a minimum viable product people actually want to use though, particularly the usage of CDNs to reduce latency. However I haven't heard much about the details regarding ssr/issr vs ssg though, so if you have any reading that elaborates more on it I'd love to take a look.

Additionally, taking this scaled t-shirt app approach as a template can you share any insight into how a more complicated platform (eg Youtube, Amazon) would further leverage such in-house/3rd party services to most efficiently use their resources (ie at the fully mature platform stage)?