TLDR: Here's the commit that I made all code changes in

I recently updated the version of sveltekit I'm using for qr-gen, and it was quite the experience :). There's not much documentation out there (at least that I could find), so I'm documenting what I needed to change here.

Update dependencies

yarn add @sveltejs/kit@latest @sveltejs/adapter-auto@latest --exact

Note: if you're using any other packages under the @sveltejs org, you'll likely need to update those as well.

Add vite.config.js

Next, I needed to create vite.config.js in the root of the repo and add the svelte-kit plugin to the config:

import {sveltekit} from '@sveltejs/kit/vite'

/** @type {import('vite').UserConfig} */
const config = {
  plugins: [sveltekit()]
}

export default config

You'll also need to remove any configuration you have under the kit.vite property in svelte.config.js. Consulting the vite configuration docs should be helpful here.

Update API Routes to Use Uppercase Method Names

Updating export const post to export const POST (and so forth for other request methods)