Tough call, but if it were up to you, which CMS would you choose for a landing page and why?
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I'd build with astro.build (because it's super performant and light on JS) and probably avoid using a CMS altogether. If a CMS was absolutely needed, I'd integrate with sanity.io because it's so flexible and nice to work with.
I really like working with Astro, and if it's for a site where other people are working on it, or the site's too big or too dynamic to make easily I usually end up using it. Astro SSR is awesome when I don't wanna do SSR manually, but I avoid it for static sites