Just to follow up on this. I wrote a little CRUD app (managing a list of users). I wrote it in both preact and in svelte, wanting to see how the two grew as I added new features.
When adding the "Edit User" feature:
Svelte's unminified size grew 1.39x. Its min+gzip grew 1.2x.
Preact's unminified size grew 1.06x. Its min+gzip grew 1.05x.
The final tally for an almost line-for-line equivalent app in both:
Preact:
- Minified: 15.8KB
- Min+GZ: 6.2KB
Svelte:
- Minified: 23KB
- Min+GZ: 4.8KB
So for a trivially small app, when minified and gzipped, Svelte does produce very compact results. But its growth rate (1.2x) vs preacts (1.05x) indicates to me that it would probably outgrow preact on a normal-sized app.
It would take a long time for it to outgrow the typical React or Angular stack, though.
My conclusion was that it seemed like the file size would grow fairly quickly
[1](https://www.reddit.com/r/javascript/comments/5fcwhz/svelte_t...)