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Edge Prerendering

Prerender pages at deploy time so the first visitor receives cached HTML.

Static pages (no params)

Export prerender = true from the companion .server.ts file:

// pages/about.server.ts
export const prerender = true;

Pages without dynamic params do not need getPrerenderPaths().

Dynamic pages (with params)

For pages with URL params, also export getPrerenderPaths() to specify which param combinations to prerender. Annotate the return type with PageParams for that page's URL pattern, such as /blog/:slug for pages/blog/[slug].server.ts. TypeScript then requires each object to include those params, so a missing or misspelled key is a type error. Void does not infer this type from the filename.

// pages/blog/[slug].server.ts
import type { PageParams } from 'void/routes';

export const prerender = true;

export async function getPrerenderPaths(): Promise<PageParams<'/blog/:slug'>[]> {
  return [{ slug: 'hello-world' }, { slug: 'getting-started' }];
}

Each object must include every param in the page path. Values can be strings or numbers, and Void URL-encodes them. A single-segment param such as [slug] cannot contain /. For nested paths, use a catch-all page such as pages/docs/[...slug] and return { slug: 'guides/intro' }. If an entry is invalid, void deploy fails. The error names the server file and the entry index.

Custom SSR

In custom SSR mode (src/main.ssr.ts), export getPrerenderPaths() at the top level. Since there's no file-based routing, return full path strings:

// src/main.ssr.ts
export const prerender = true;

export async function getPrerenderPaths(): Promise<string[]> {
  return ['/', '/about', '/blog/hello-world'];
}

Annotate this return type as an array of path strings. Use PageParams on file-based pages, where the function returns param objects.

Relationship to revalidation

Setting routing.isr: false in void.config.ts disables ISR and this edge-prerendering behavior, including per-page exports. It does not disable build-time HTML generation with output: "static".

Prerendered pages default to a one-year revalidate TTL. Deploys clear the ISR cache.

Override the TTL per page:

// pages/about.server.ts
export const prerender = true;
export const revalidate = 3600;

If the cached page expires before your next deploy, the next request waits for a fresh render.

Behavior details

  • Prerender happens once per deployment, before traffic is routed to the new version. Prerendered pages are cached at the edge.
  • Only paths with a positive revalidate TTL are prerendered (TTL 0 is skipped).
  • Prerender failures are logged but never block the deploy. The page will render on the first request as usual.