ISR (Incremental Static Regeneration)
GlossaryA Next.js feature that serves a cached static page and regenerates it in the background when stale.
Definition
Incremental Static Regeneration (ISR) is a Next.js feature that lets you pre-render a subset of pages at build time and serve cached versions for the rest, regenerating them on-demand after a `revalidate` interval. FormLoom's `/[framework]/[form-type]` matrix uses ISR: the top 8 frameworks × 10 form types (80 pages) are pre-rendered at build, and the remaining 140 combinations are served on-demand via ISR.
Why it matters for form backends
ISR keeps `pnpm build` fast even when the full route matrix implies thousands of pages — pre-render the high-value subset, ISR the long tail.
FAQ
86400 seconds (24 hours) — enough to serve cached pages fast while picking up data updates daily.
Related terms
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