Deploying SvelteKit

SvelteKit runs on slew's Node servers through the official Node adapter.

Build with adapter-node

npm i -D @sveltejs/adapter-node

// svelte.config.js
import adapter from '@sveltejs/adapter-node'

export default {
  kit: { adapter: adapter() },
}

npm run build produces build/ with index.js as the entry. It reads PORT from the environment and binds 0.0.0.0 by default — exactly what the platform injects, so no host configuration is needed.

Push to GitHub — detected automatically

Connect the repo and every push deploys. The builder recognizes an adapter-node build — the dependencies plus build/index.js — and assembles the server artifact for you: the build as the server bundle, your package.json next to the entry (the build is ESM in .js files and needs "type": "module"), a production node_modules from your lockfile (npm ci --omit=dev, so commit a package-lock.json), and build/client/ served straight from the CDN. Leave the build settings at their defaults.

Set ORIGIN so SvelteKit knows its public URL (form actions and absolute URLs depend on it), then connect:

slew env set ORIGIN=https://<project>.slew.cloud
slew git connect owner/repo

Fingerprinted assets under /_app/* are served from static/ by the CDN; everything else hits the SvelteKit server. Keep production dependencies lean — the deploy caps at 10,000 files, node_modules included.

The manual artifact (fallback and reference)

An explicit slew.json in the output directory always wins over detection. Two runtime needs shape the artifact:

• The build is ESM in .js files, so Node needs a "type": "module" package.json next to the entry — copy the project's into the artifact.
• Packages in your dependencies stay external and resolve from node_modules at runtime (devDependencies are bundled into the build). Ship a pruned node_modules — via git push-to-deploy, because slew deploy never packs node_modules.

slew.json              { "server": "server/index.js" }
server/                = build
server/package.json    the project package.json ("type": "module")
server/node_modules/   production dependencies
static/                = build/client — served directly by the CDN

Assembly (scripts/build-slew.sh or an npm script):

npm run build
npm ci --omit=dev
rm -rf out && mkdir out
cp -r build out/server
cp package.json out/server/package.json
cp -r node_modules out/server/node_modules
cp -r build/client out/static
printf '{ "server": "server/index.js" }\n' > out/slew.json

Connect with the assembly as the build command:

slew git connect owner/repo --build-cmd "bash scripts/build-slew.sh" --output out

slew deploy out also works — but only when the app has nothing in dependencies, since the CLI strips node_modules. With an empty dependencies the build is fully self-contained and you can skip the node_modules copy.