Using Different Servers with Svelte

Assumptions

We won't go over installing Express or Polka here.

Using adapter-node

• Building SvelteKit for Node JS To use an alternative Node.JS server first, you will need to build your application for Node using the adapter-node package. Follow the linked tutorial, then proceed.

Using Express

After building the application for node, Svelte will output two files, handler.js and index.js. The handler.js file will be the file you pass into Express as middleware.

Next, make a new file and paste the following code into it. This import the handler.js file into an express server and adds a /healthcheck route then starts the server on port 3000. If you built the application in a different directory make sure to change the ./build/handler.js route.

javascript
import { handler } from './build/handler.js';
import express from 'express';
 
const app = express();
 
// add a route that lives separately from the SvelteKit app
app.get('/healthcheck', (req, res) => {
  res.end('ok');
});
 
// let SvelteKit handle everything else, including serving prerendered pages and static assets
app.use(handler);
 
app.listen(3000, () => {
  console.log('listening on port 3000');
});

Using Polka

Polka and Express have very simular APIs, which makes using them interchangeably very easy. To use polka simply replace the import statement for express with polka and everything will work.