Hi, @tenders64, I want to make it clear that you don’t have to use any static site generator or framework to make a JAMstack site.
You can write your own HTML, CSS, and javascript from scratch and make a JAMstack site. You can then just link to your Git repo and deploy the site code (with no build step).
In that case you are not committed to anything. No javascript library. No frameworks. You are going to create an entire site from scratch including every single line of code required to implement your goal.
While this involves the least commitment it is also probably a lot of work. Do you really want to write you own jquery or graphql libraries from scratch?
For example, while it isn’t completely impossible that I could personally write a better jquery, I consider it very unlikely (“very, very” - probably 6 "very"s total - that is six sigmas of uncertainty) that I actually would write a better library if I attempted to. Again, many people worked hard inventing and polishing that wheel already.
Writing a library isn’t my goal, making a website is. Then again, maybe writing your own libraries is your goal. Someone wrote jquery after all.
The reason that people use static site generators (SSGs) is so that they don’t need to reinvent the wheel. The boilerplate code for the site is created for you and you can focus on building site content and behavior instead of writing javascript helper functions that already exist.
My point? You are going to end up committing to something if you want to get the efficiency an SSG and/or javascript framework offers. I recommend spending some time researching what you want to learn so you pick something you enjoy and that will teach you skill you can (hopefully) reuse in the future.
You might want to research the frameworks available a decide which one you want to learn. Maybe Vue or React?
If Vue is interesting to you and a tool you want to keep using in the future then maybe look at Nuxt? Is React more your style? Then maybe Gatsby would suit you.
Maybe you are also working with Ruby. If so, you might enjoy using Jekyll.
Please don’t take those examples as my recommendations for you. I’m only trying to point out that what is best for you is likely going to depend on and overlap with your other interests.
The best lightweight framework for me isn’t going to be the same best lightweight framework for you. If you tell us more about what your interests are, it might help someone recommend something specific to your tastes and skillset. What do you want to learn?
I realize you were asking for answers and I just gave you more questions which is the opposite. This is the best answer I have though: ‘it depends’.