svelte 5 or vue 3.5 for two devs shipping an internal dashboard in six weeks Vue

I won't, and for a reason you named and then argued past: heavy tables and charts.

On a dashboard, the code you write is dominated by the table component, the date picker, form validation and the chart wrapper. Vue has several mature, complete answers for all four. Svelte has some good ones and a lot of thin ones, and "this library was last released 14 months ago" is a real six-week risk when you have 20 screens to get through.

Runes are better than Vue's reactivity by a meaningful margin, in my opinion. It doesn't matter enough here.

Vue, but for the maintenance argument rather than the library one. A contractor in 2029 opening a Vue SFC knows exactly what they're looking at. <script setup> has been stable for years and the docs are genuinely excellent.

Svelte 5 is great and I use it daily, but a contractor whose last Svelte was 4 will open your $state/$derived/$props code and lose half a day. That's a real cost you're paying with somebody else's time.

Six weeks with one dev who's React-only: whichever you pick, the risk isn't the framework, it's the build/router/state trio. Take the batteries-included path — Nuxt if Vue, SvelteKit if Svelte — and do not hand-roll routing on a deadline.

Websockets on two screens is a non-issue either way. Ten lines and a store.

Do a two-hour table spike before you commit. Load 5,000 rows with sorting, column resize and a sticky header in both and watch what happens. That single test has decided this for me twice, and not in the same direction both times.

svelte, less code, you'll ship in four weeks instead of six

Internal dashboard, six weeks, two devs — consider that the bigger question is whether you can get away without SSR. A client-rendered SPA behind auth removes an entire category of problems (hydration, server state, deployment shape) and both frameworks do that perfectly well.