SvelteKit Build Error

Hello! I am trying out Vercel (wanting to move away from Netlify) but I am not sure how to get my SvelteKit app to successfully deploy. I am hoping someone can help here.

Build fails and I would like to see a successful build

import adapter from ‘@sveltejs/adapter-auto’
import { vitePreprocess } from ‘@sveltejs/kit/vite’

/** @type {import(‘@sveltejs/kit’).Config} */
const config = {
preprocess: [vitePreprocess({})],
kit: {
// adapter-auto only supports some environments, see Zero-config deployments • Docs • Svelte for a list.
// If your environment is not supported or you settled on a specific environment, switch out the adapter.
// See Adapters • Docs • Svelte for more information about adapters.
adapter: adapter({
runtime: ‘nodejs22.x’,
}),
alias: {
$lib: ‘src/lib’,
$components: ‘src/lib/components’,
$routes: ‘src/routes’,
},
},
}

export default config

Here is the error I get:

error during build:
TypeError: builder.findServerAssets is not a function or its return value is not iterable

at generate_serverless_function (file:///vercel/path0/node_modules/.pnpm/@sveltejs+adapter-vercel@5.7.2_@sveltejs+kit@1.30.4_rollup@3.29.5/node_modules/@sveltejs/adapter-vercel/index.js:109:33)

at async Object.adapt (file:///vercel/path0/node_modules/.pnpm/@sveltejs+adapter-vercel@5.7.2_@sveltejs+kit@1.30.4_rollup@3.29.5/node_modules/@sveltejs/adapter-vercel/index.js:334:5)

at async adapt (file:///vercel/path0/node_modules/.pnpm/@sveltejs+kit@1.30.4_svelte@4.2.19_vite@4.5.9/node_modules/@sveltejs/kit/src/core/adapt/index.js:37:2)

at async finalise (file:///vercel/path0/node_modules/.pnpm/@sveltejs+kit@1.30.4_svelte@4.2.19_vite@4.5.9/node_modules/@sveltejs/kit/src/exports/vite/index.js:810:7)

at async Object.handler (file:///vercel/path0/node_modules/.pnpm/@sveltejs+kit@1.30.4_svelte@4.2.19_vite@4.5.9/node_modules/@sveltejs/kit/src/exports/vite/index.js:840:5)

at async PluginDriver.hookParallel (file:///vercel/path0/node_modules/.pnpm/rollup@3.29.5/node_modules/rollup/dist/es/shared/node-entry.js:25466:17)

at async Object.close (file:///vercel/path0/node_modules/.pnpm/rollup@3.29.5/node_modules/rollup/dist/es/shared/node-entry.js:26726:13)

at async build (file:///vercel/path0/node_modules/.pnpm/vite@4.5.9_@types+node@20.17.16/node_modules/vite/dist/node/chunks/dep-3936e161.js:48098:13)

at async CAC. (file:///vercel/path0/node_modules/.pnpm/vite@4.5.9_@types+node@20.17.16/node_modules/vite/dist/node/cli.js:843:9)

ELIFECYCLE Command failed with exit code 1.

Error: Command “pnpm run build” exited with 1

Svelte 4.2.19
SvelteKit 1.20.4
PNPM
Vite

Hey, this looks like a version mismatch issue – you’re using the latest Vercel Adapter but your @svelte/kit package is quite old

findServerAssets was added in @svelte/kit@2 so you’ll either need to

  • update to @sveltjs/kit@latest
  • or roll back to @sveltejs/adapter-vercel@3.1.0