Deploy SvelteKit with SSR on Coolify (Hetzner VPS)

This is my first quick try deploying SvelteKit with the open source software Coolify by Andras Bacsai. Coolify is an "open-source & self-hostable Heroku / Netlify / Vercel alternative".

The advantage of Coolify compared to (also awesome) server management tools like ploi.io (SvelteKit ploi.io tutorial), cleavr or Laravel Forge is that you can install it directly on your VPS without additional subscription costs. This is especially great for low budget / small hobby projects.

Specs:

• VPS: Hetzner Cloud CPX11 (AMD) - €4,35/month - Update: ARM might be a faster choice
• Coolify v4.0.0-beta.269

Disclaimer: If you want to use this setup in production, please take measures to secure your VPS.

Install selfhosted Coolify on Hetzner VPS

Just create a new CPX11 cloud server on hetzner, connect via SSH (ssh root@your-server-ip) and run the command from https://coolify.io/self-hosted:

curl -fsSL https://cdn.coollabs.io/coolify/install.sh | bash

That's really it. After install, you can create your admin user via http://your-vps-server-ip:8000/. See slightly older YouTube video for full example: https://www.youtube.com/watch?v=Jg6SWqyvYys

Prepare the SvelteKit demo app

You can also use my demo repository: https://github.com/mandrasch/sveltekit-demo-app-adapter-node

Create a git repository, use the official SvelteKit installer, select demo app when asked: npm create svelte@latest . Install dependencies via npm i.

Important: Install adapter-node via npm i -D @sveltejs/adapter-node and switch from adapter-auto to adapter-node in svelte.config.js:

import adapter from '@sveltejs/adapter-node';

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

This is needed for SSR support on Coolify. See SvelteKit docs for more information on adapter-node: https://kit.svelte.dev/docs/adapter-node

Commit and push all your changes to your GitHub repository.

Create a new project in Coolify

Let's get the party started by creating a new project:

Select production:

Add a new resource:

Select "public repository":

Select localhost and destination, there is only one option to select anyway ;-)

Paste your repository URL, I used my repository https://github.com/mandrasch/sveltekit-demo-app-adapter-node:

Click "check" and continue with these default settings:

Now we configure the install, build and start command. Use the following commands:

• Install: npm ci --omit dev
• Build: npm run build
• Start: node build

Important: Don't forget to hit "Save" (!)

See SvelteKit docs for more information about these commands: https://kit.svelte.dev/docs/adapter-node

Switch to https and set ORIGIN

The deployment with http:// would be okay, but two important things are missing:

• https support, otherwise cookies won't work
• setting the ORIGIN (via environment variables)

For https, just switch the temporary sslip.io domain to https:// and hit 'Save'(!):

Now we need to set the ORIGIN, otherwise SvelteKit can't really detect its own domain - this will likely cause Cross-site POST form submissions are forbidden errors.

Important: The node-adapter docs state that you can use ORIGIN=... node build as start command, but this did not work on Coolify (guess because of Docker).

Instead add a new env variable here (!):

Now it's time for the first deployment, just hit the "Deploy" button and use "Show debug logs" for all information:

Don't get confused by red error messages, I guess these are false positives:

After this is finished, the status in Coolify should switch to "Running" and you should able to play Sverdle (which is implemented via SSR) on your newly created site 🎉

Have fun with selfhosting!

Connect a domain

You can set the domain of your coolify instance in Settings, just point an A-Record to your servers IP.

You can also point *.my-coolify-server.example.com to your server and use this as wildcard for project URLs.

Let's encrypt HTTPS certificates are managed automatically by Coolify.

Troubleshooting: Out of memory

I sometimes ran into "502 Bad Gateway" and 200% CPU load after hitting "Deploy" - while I had other (PHP + MySQL) resources running on my Coolify instance. I asked the Coolify Developer on GitHub and he gave me multiple suggestions.

Decided to try the swap option. Swap is disabled by default on Hetzner VPS (see: reddit discussion)
I followed this guide (for ubuntu) and added 6GB swap space (since I only had 17G left on my small VPS) https://www.digitalocean.com/community/tutorial-collections/how-to-add-swap-space.

Multiple projects running + builds at the same time now seem to work fine now. 🎉

See Coolify requirements for more information. The good thing is that you can always upscale/downscale the resources for Hetzner Cloud VPS (as far as I know).

Docs and resources:

• https://coolify.io/docs/resources/applications/svelte-kit
• https://kit.svelte.dev/docs/adapter-node
• https://nixpacks.com/docs/providers/node
• Coolify crash course Self Host 101 - Set up Coolify | Self Hosted PaaS with Zero Config Deployments (YouTube)
• General tutorial: Deploy Node.js applications on a VPS using Coolify
• 5 Easy Steps to Secure your Cloud Server 🔒