HTML.

Unironically have been migrating my static pages (from Nextjs and Eleventy) to plain HTML and love it. Of course depends on your use case if that is feasible.

I recently rebuilt my site with Parcel + React Server Components. RSC are designed to solve many of the same problems that Astro does. And Parcel is “just” a bundler and not a framework, so it has less magic and gives you more control.

https://micahcantor.com/blog/rsc-rewrite.html

Mastering HTML, CSS and vanilajs.

Then one is pretty much safe from framework tides.

I experimented a lot with bootstrapping React projects this past fall, and Astro was by far the least painful to use. Notably, it was the least goofy of all of the React starter kits to use for server API development.

https://lume.land/ a good, straightforward SSG.

There's one other I've seen recently that looked good but I have misplaced the link

Eleventy, of course :-)

But why are you looking for alternatives already?

Well, there's this other project that recently secured funding from a company that has a proven track record of supporting great open-source projects like Astro, TanStack, and Hono without trying to capture or lock anything down.

There's even an article about it somewhere.