We build with both. The choice is boring and mechanical once you ask the right question: how much of the page changes per user?
Choose Astro when content leads
Marketing sites, documentation, blogs, landing pages — anything where most visitors see the same HTML. Astro ships zero JavaScript by default and hydrates only the islands that need it. That’s how you get Lighthouse scores near 100 without a performance sprint at the end of the project.
Choose Next.js when state leads
Dashboards, logged-in products, anything with per-user data on most routes. Server components, streaming and a mature auth ecosystem make Next.js the safer foundation for application-shaped software.
The hybrid we ship most often
For SaaS clients we usually pair them: an Astro marketing site on the apex domain
(fast, cheap to host, easy to iterate on SEO) and a Next.js app on app. — each
deployed independently on EU infrastructure. Your marketing team never blocks a
product release again, and vice versa.