Let us explain what the ‘JAM stack’ is for people that, maybe, need to understand it better. So basically, the JAMstack itself is mostly a name for a way of approaching the architecture of building web projects.
There’s just no way at the moment to get make them even faster.
Because of this kind of pre-built, the application or site can be ‘serverless’. Of course, this does not mean the application will spin up without a server. It simply means that the code does not require a server 24/7 and only ‘calls’ on the server when necessary. Therefore, you as a site owner or developer, don’t have to worry about building and maintaining the stability of the application. Simply put, you just serve it. Even with something as complex as hosting the site, it is that simple. To strengthen and quicken this, a content delivery network can be used. These are geographically spread proxy servers on the internet stored in data centers. The CDN helps to store and deliver content fast, or better said, very fast.
To summarize, make sure that everything is pre-built and ready on a CDN as performant as possible. In that scenario, you (sort of) end up with the best of both worlds.
It’s a complicated system, but this should’ve helped you a bit.