svelte@5.56.0

sveltejs/sveltesvelte@5.56.0May 29, 2026by github-actions[bot]

AI Summary

A minor release introducing declarations directly inside the template and multiple performance optimizations to improve rendering efficiency.

Key Highlights

Allow declarations (let/const) in the template body
Performance improvements using `createElement` for HTML elements
Store `current_sources` as a Set for O(1) membership checks
Deduplicate identical hoisted templates within components

New Features

Allow declarations in the template

Full Release Notes

### Minor Changes

-   feat: allow declarations in the template ([#18282](https://github.com/sveltejs/svelte/pull/18282))

### Patch Changes

-   perf: use `createElement` instead of `createElementNS` for HTML elements ([#18262](https://github.com/sveltejs/svelte/pull/18262))

-   perf: store `current_sources` as a `Set` for O(1) membership checks ([#18278](https://github.com/sveltejs/svelte/pull/18278))

-   perf: deduplicate identical hoisted templates within a component ([#18320](https://github.com/sveltejs/svelte/pull/18320))

-   perf: hoist `rest_props` exclude list as a module-scope `Set` ([#18252](https://github.com/sveltejs/svelte/pull/18252))