Using sequence means I need to include @sveltejs/kit in my Node Docker image

[Karlinator]

Describe the problem

I noticed when trying to slim down my Docker images that if I kept only the runtime dependencies after building (which I list in dependencies and install with npm ci --only=prod) my container would immediately crash because it Cannot find package '@sveltejs/kit' imported from /usr/srv/build/server/app.js.

It turns out that when you use sequence() for hooks, the generated app.js file includes import { sequence } from '@sveltejs/kit/hooks.

Describe the proposed solution

I'm not sure how, but it would be nice if we copied over the relevant code (the 26 lines from https://github.com/sveltejs/kit/blob/master/packages/kit/src/hooks.js) in the build or something so I don't have to include the entirety of SvelteKit in my runtime.

Not sure if this is Kit or the adapter.

Alternatives considered

I can just live with it. It's just ~2MB of the total image size.

Importance

nice to have

Additional Information

No response

[Conduitry]

This sounds like it's essentially the same as #3176.

[Karlinator]

Almost entirely (I didn't see it when searching). It would solve this, but I guess it is possible to solve this without also solving #3176 (this is essentially a narrower issue I encountered while working around that issue).

[Rich-Harris]

https://kit.svelte.dev/docs#modules-sveltejs-kit-hooks is an anomaly in that it's the only SvelteKit-provided module that stays in your node_modules rather than essentially become part of your source code (which we do because the behaviour of functions like goto depends on the structure of your app). One way to fix this would be to turn it into $app/hooks or something instead

[Conduitry]

I don't think that would be the correct fix, because I think the correct fix would be to address #3176 and not force people to do that in userland. Dev dependencies of your app shouldn't be required in production, and the build should take that into account when bundling stuff. Moving this into $app just so that we can avoid addressing that other issue seems like the wrong solution.

[Karlinator]

I checked quickly and what adapter-cloudflare does is buindle this little snippet into the worker script, along with every other runtime dependency (so what #3176 wants to do with adapter-node). I think that's a much better overall solution, removing the need for any finicky dependency management like I currently do in my Dockerfile to try to not keep any unneeded dependencies.

Moving sequence to $app/hooks wouldn't be the worst idea anyway—as you say it's the only part of SvelteKit runtime code that stays in node_modules.

[silentworks]

I ran into this issue today. I've for now moved my @sveltejs/kit to be a dependency to solve the issue for now.

[Rich-Harris]

Going to close this in favour of #3176, as the solution to that would cover this issue. I don't think there's much mileage in applying a narrower fix here (though now that I think about it, @sveltejs/kit is now always marked as noExternal when building, so this is probably already fixed)