SvelteKit 2.70

Apply the Svelte 5.57, Node.js 24, TypeScript 6.0, and JavaScript ES2026 prompts first. These rules cover @sveltejs/kit 2.70.3 in the SvelteKit 2.70 release line. Apply Node-specific adapter settings only to Node deployments.

Version and effective configuration

• Run the newest SvelteKit 2 release and rebuild deployment artifacts after each upgrade. SvelteKit has published each fix as a new release at the head of its line, not a patch to an older minor, so take a fix by moving to the release the advisory lists, even a newer minor than 2.70. Update and audit adapters separately: @sveltejs/adapter-node, @sveltejs/adapter-vercel, and the others are versioned apart from @sveltejs/kit, which doesn't move them.
• Match Svelte, Vite, @sveltejs/vite-plugin-svelte, TypeScript, and adapter peer requirements to the deployed toolchain. Use the included maintained Node.js 24 baseline; Kit's node >=18.13 package floor does not make end-of-life Node releases suitable for production.
• Review the configuration actually used by the sveltekit(...) Vite plugin. Supplying configuration there overrides svelte.config.js; ensure CSP, CSRF, environment, and experimental settings are applied in the effective configuration.

Private modules and environment values

• Put privileged helpers in $lib/server or files named *.server.js/*.server.ts, and use +page.server/+layout.server for privileged loads. Keep their imports out of universal +page/+layout modules and components, including indirect imports. Run a production build with TEST unset: illegal server-only