Astro popularizes selective hydration
Jamund Ferguson, senior engineer at PayPal, on using Jamstack in the enterprise
This shift matters because it marks the point where Jamstack stopped meaning ship a big React app to every browser, and started meaning ship mostly HTML, then add JavaScript only where a page actually needs it. Astro pushed that model into the mainstream with islands architecture, while Gatsby’s original model relied on broader React hydration, which often meant more client JavaScript and more work before a page felt interactive. That matters most on content, docs, marketing, and ecommerce pages where speed drives SEO and conversion.
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Astro’s core idea is selective hydration. A page can render as static HTML, then only hydrate small interactive widgets like a search box, carousel, or comments module. If a widget never appears on screen, its JavaScript may never load at all.
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Gatsby helped popularize static React sites, but its standard model hydrates the page into a React app on the client. Gatsby later added partial hydration, which shows the market moved toward Astro’s lighter weight approach rather than away from the performance problem entirely.
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The business driver underneath the tooling debate is Google’s emphasis on Core Web Vitals. Lower JavaScript payloads generally help pages load faster, respond faster, and shift less on screen, which is why teams in SEO heavy categories keep pushing toward simpler rendering models.
Going forward, the winning web stack is likely to look more hybrid. Static HTML will remain the default for pages that mostly publish information, while interactivity gets added in small targeted pieces. That favors frameworks like Astro, and it also pushes heavier React frameworks to adopt similar patterns so they can keep up on speed.