# Svelte changelog

> Cybernetically enhanced web apps.

- Vendor: Svelte
- Category: Frameworks & Libraries
- Official site: https://svelte.dev
- Tracked by: What's New (https://whatsnew.fyi/product/svelte)
- Harvested from: GitHub (sveltejs/svelte)
- Entries below: 25 (newest first)

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

## Releases

### 5.56.8

- Date: 2026-07-24
- Version: 5.56.8
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.56.8
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.56.8

- **fixed** — Call `onerror` and provide a working `reset` when hydrating a failed boundary
- **fixed** — Preserve select selection when spread attributes omit value

###### Patch Changes

-   fix: call `onerror` and provide a working `reset` when hydrating a failed boundary ([#18556](https://github.com/sveltejs/svelte/pull/18556))

-   fix: preserve select selection when spread attributes omit value ([#18561](https://github.com/sveltejs/svelte/pull/18561))

### 5.56.7

- Date: 2026-07-20
- Version: 5.56.7
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.56.7
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.56.7

- **added** — Provide `indent` option for `print`

###### Patch Changes

-   chore: provide `indent` option for `print` ([#18474](https://github.com/sveltejs/svelte/pull/18474))

### 5.56.6

- Date: 2026-07-16
- Version: 5.56.6
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.56.6
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.56.6

- **fixed** — rerun derived that had an abort controller on reconnection
- **changed** — skip unnecessary blocker analysis when compiling components without top-level await

###### Patch Changes

-   perf: skip unnecessary blocker analysis when compiling components without top-level await ([#18548](https://github.com/sveltejs/svelte/pull/18548))

-   fix: rerun derived that had an abort controller on reconnection ([#18551](https://github.com/sveltejs/svelte/pull/18551))

### 5.56.5

- Date: 2026-07-14
- Version: 5.56.5
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.56.5
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.56.5

- **fixed** — Don't (re)connect deriveds when read inside branch/root effects
- **fixed** — Skip unnecessary derived effect in earlier batch
- **fixed** — Avoid declaration tag warning in event handlers
- **fixed** — Abort deriveds own AbortSignal when it disconnects
- **fixed** — Ensure $state.eager() is correctly transformed for SSR output
- **fixed** — Correctly transform declaration tags during SSR
- **fixed** — Transform computed keys in keyed {#each} destructuring patterns
- **fixed** — Chain preprocessor sourcemaps with an empty sources[0] instead of dropping them
- **fixed** — Clear previous_task reference after abort in Tween to prevent memory leak on interrupted tweens
- **fixed** — Don't treat declaration tags as parts inside each blocks

###### Patch Changes

-   chore: drop dead code that make TSGO fail ([#18496](https://github.com/sveltejs/svelte/pull/18496))

-   fix: don't (re)connect deriveds when read inside branch/root effects ([#18527](https://github.com/sveltejs/svelte/pull/18527))

-   fix: skip unnecessary derived effect in earlier batch ([#18525](https://github.com/sveltejs/svelte/pull/18525))

-   fix: avoid declaration tag warning in event handlers ([#18500](https://github.com/sveltejs/svelte/pull/18500))

-   fix: abort deriveds own AbortSignal when it disconnects ([#18400](https://github.com/sveltejs/svelte/pull/18400))

-   fix: ensure `$state.eager()` is correctly transormed for SSR output ([#18530](https://github.com/sveltejs/svelte/pull/18530))

-   fix: correctly transform declaration tags during SSR ([#18492](https://github.com/sveltejs/svelte/pull/18492))

-   fix: transform computed keys in keyed `{#each}` destructuring patterns ([#18521](https://github.com/sveltejs/svelte/pull/18521))

-   fix: chain preprocessor sourcemaps with an empty `sources[0]` instead of dropping them ([#18518](https://github.com/sveltejs/svelte/pull/18518))

-   fix: clear previous_task reference after abort in Tween to prevent memory leak on interrupted tweens ([#18541](https://github.com/sveltejs/svelte/pull/18541))

-   fix: don't treat declaration tags as parts inside each blocks ([#18507](https://github.com/sveltejs/svelte/pull/18507))

### 5.56.4

- Date: 2026-06-23
- Version: 5.56.4
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.56.4
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.56.4

- **fixed** — Include wrapping parentheses in {@const} declarator end position
- **fixed** — Always unset reactivity context after restoring it
- **fixed** — Don't notify searchParams subscribers when the URL changes without affecting the search string
- **fixed** — Strip ? from optional parameters in <script lang="ts"> so generated JavaScript is valid

###### Patch Changes

-   fix: include wrapping parentheses in `{@const}` declarator `end` position ([#18436](https://github.com/sveltejs/svelte/pull/18436))

-   fix: always unset reactivity context after restoring it ([#18453](https://github.com/sveltejs/svelte/pull/18453))

-   fix: don't notify `searchParams` subscribers when the URL changes without affecting the search string ([#18425](https://github.com/sveltejs/svelte/pull/18425))

-   fix: strip `?` from optional parameters in `<script lang="ts">` so generated JavaScript is valid ([#18448](https://github.com/sveltejs/svelte/pull/18448))

### 5.56.3

- Date: 2026-06-07
- Version: 5.56.3
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.56.3
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.56.3

- **fixed** — Ignore errors that occur in destroyed effects
- **fixed** — Type BigInts in $state.snapshot(...) return values

###### Patch Changes

-   fix: ignore errors that occur in destroyed effects ([#18384](https://github.com/sveltejs/svelte/pull/18384))

-   fix: type BigInts in `$state.snapshot(...)` return values ([#18388](https://github.com/sveltejs/svelte/pull/18388))

### 5.56.2

- Date: 2026-06-04
- Version: 5.56.2
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.56.2
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.56.2

- **fixed** — Properly track effect end node for async sibling component
- **fixed** — Prevent false-positive reactivity loss warning
- **fixed** — Ignore declaration tags for animation directive
- **fixed** — Reject pending async deriveds on discard

###### Patch Changes

-   fix: properly track effect end node for async sibling component ([#18371](https://github.com/sveltejs/svelte/pull/18371))

-   fix: prevent false-positive reactivity loss warning ([#18373](https://github.com/sveltejs/svelte/pull/18373))

-   chore: bump esrap dependency ([#18372](https://github.com/sveltejs/svelte/pull/18372))

-   fix: ignore declaration tags for animation directive ([#18366](https://github.com/sveltejs/svelte/pull/18366))

-   fix: reject pending async deriveds on discard ([#18308](https://github.com/sveltejs/svelte/pull/18308))

### 5.56.1

- Date: 2026-06-01
- Version: 5.56.1
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.56.1
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.56.1

- **fixed** — Error at compile time on duplicate snippet/declaration tag definitions
- **fixed** — Parse declaration tag contents more robustly
- **fixed** — Correctly transform references to earlier declarators in a declaration tag
- **fixed** — Avoid spurious state_referenced_locally warnings for $derived declarations in declaration tags
- **fixed** — Tolerate whitespace before let/const in declaration tags
- **fixed** — Prevent infinite loop when a tag's expression ends with a trailing / at the end of the input
- **fixed** — More robust parsing of declaration tags with regards to type
- **fixed** — Preserve newlines in spread input values when the type attribute is applied after value
- **fixed** — Update SvelteURLSearchParams when setting duplicate keys to the same joined value
- **fixed** — Check references for blockers on server, too

###### Patch Changes

-   fix: error at compile time on duplicate snippet/declaration tag definitions ([#18351](https://github.com/sveltejs/svelte/pull/18351))

-   fix: parse declaration tag contents more robustly ([#18353](https://github.com/sveltejs/svelte/pull/18353))

-   fix: correctly transform references to earlier declarators in a declaration tag (e.g. `{let a = $state(0), b = $derived(a * 2)}`) ([#18348](https://github.com/sveltejs/svelte/pull/18348))

-   fix: avoid spurious `state_referenced_locally` warnings for `$derived` declarations in declaration tags ([#18348](https://github.com/sveltejs/svelte/pull/18348))

-   fix: tolerate whitespace before `let`/`const` in declaration tags ([#18348](https://github.com/sveltejs/svelte/pull/18348))

-   fix: prevent infinite loop when a tag's expression ends with a trailing `/` at the end of the input ([#18350](https://github.com/sveltejs/svelte/pull/18350))

-   fix: more robust parsing of declaration tags with regards to `type` ([#18330](https://github.com/sveltejs/svelte/pull/18330))

-   fix: preserve newlines in spread input values when the `type` attribute is applied after `value` ([#18345](https://github.com/sveltejs/svelte/pull/18345))

-   fix: update `SvelteURLSearchParams` when setting duplicate keys to the same joined value ([#18336](https://github.com/sveltejs/svelte/pull/18336))

-   fix: check references for blockers on server, too ([#18352](https://github.com/sveltejs/svelte/pull/18352))

### 5.56.0

- Date: 2026-05-29
- Version: 5.56.0
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.56.0
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.56.0

- **added** — Allow declarations in the template
- **changed** — Use createElement instead of createElementNS for HTML elements
- **changed** — Store current_sources as a Set for O(1) membership checks
- **changed** — Deduplicate identical hoisted templates within a component
- **changed** — Hoist rest_props exclude list as a module-scope Set

###### 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))

### 5.55.10

- Date: 2026-05-27
- Version: 5.55.10
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.10
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.55.10

- **fixed** — Unlink errored and otherwise finished batch
- **changed** — Walk composedPath() directly in delegated event propagation for improved performance
- **fixed** — Transfer effects when merging batches
- **fixed** — Allow $derived(await ...) in disconnected effect roots
- **fixed** — Remove temporary raw-text hydration markers
- **fixed** — Propagate async @const blockers through closure references so template expressions like {(() => host)()} correctly wait for the awaited value
- **fixed** — Properly unlink batches
- **fixed** — Settle discarded batch
- **fixed** — Declare let: directives before {@const} declarations on slotted elements
- **fixed** — Resume outro-ed branches if they were kept around
- **fixed** — Avoid waterfall-warning when async resolves to same value
- **fixed** — Correctly coordinate component-level effects inside async blocks
- **fixed** — Make unnecessary commit work less likely
- **changed** — Add tag name to a11y_click_events_have_key_events warning
- **fixed** — Catch rejected promises while merging/committing

###### Patch Changes

-   fix: unlink errored and otherwise finished batch ([#18264](https://github.com/sveltejs/svelte/pull/18264))

-   perf: walk composedPath() directly in delegated event propagation ([#18268](https://github.com/sveltejs/svelte/pull/18268))

-   fix: transfer effects when merging batches ([#18254](https://github.com/sveltejs/svelte/pull/18254))

-   fix: allow `$derived(await ...)` in disconnected effect roots ([#18273](https://github.com/sveltejs/svelte/pull/18273))

-   fix: remove temporary raw-text hydration markers ([#18269](https://github.com/sveltejs/svelte/pull/18269))

-   fix: propagate async `@const` blockers through closure references so template expressions like `{(() => host)()}` correctly wait for the awaited value ([#18309](https://github.com/sveltejs/svelte/pull/18309))

-   fix: properly unlink batches ([#18298](https://github.com/sveltejs/svelte/pull/18298))

-   fix: settle discarded batch ([#18290](https://github.com/sveltejs/svelte/pull/18290))

-   fix: declare `let:` directives before `{@const}` declarations on slotted elements ([#18271](https://github.com/sveltejs/svelte/pull/18271))

-   fix: resume outro-ed branches if they were kept around ([#18291](https://github.com/sveltejs/svelte/pull/18291))

-   fix: avoid waterfall-warning when async resolves to same value ([#18297](https://github.com/sveltejs/svelte/pull/18297))

-   fix: correctly coordinate component-level effects inside async blocks ([#18260](https://github.com/sveltejs/svelte/pull/18260))

-   fix: make unnecessary commit work less likely ([#18263](https://github.com/sveltejs/svelte/pull/18263))

-   chore: add tag name to `a11y_click_events_have_key_events` warning ([#18272](https://github.com/sveltejs/svelte/pull/18272))

-   fix: catch rejected promises while merging/committing ([#18266](https://github.com/sveltejs/svelte/pull/18266))

### 5.55.9

- Date: 2026-05-20
- Version: 5.55.9
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.9
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.55.9

- **fixed** — Don't unset batch when calling {#await ...} promise
- **fixed** — Promise-ify {#await await ...} expressions on the server and correctly hydrate them on the client
- **fixed** — Deduplicate dependencies that are added outside the init/update cycle
- **fixed** — Avoid false-positive batch invariant error
- **fixed** — Inline primitive constants in attribute values during SSR

###### Patch Changes

-   fix: don't unset batch when calling `{#await ...}` promise ([#18243](https://github.com/sveltejs/svelte/pull/18243))

-   fix: promise-ify `{#await await ...}` expressions on the server and correctly hydrate them on the client ([#18243](https://github.com/sveltejs/svelte/pull/18243))

-   fix: deduplicate dependencies that are added outside the init/update cycle ([#18243](https://github.com/sveltejs/svelte/pull/18243))

-   fix: avoid false-positive batch invariant error ([#18246](https://github.com/sveltejs/svelte/pull/18246))

-   fix: inline primitive constants in attribute values during SSR ([#18232](https://github.com/sveltejs/svelte/pull/18232))

### 5.55.8

- Date: 2026-05-18
- Version: 5.55.8
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.8
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.55.8

- **fixed** — Handle svelte:body and fix keyframe percentage double-printing
- **fixed** — Execute uninitialized derived even if it's destroyed
- **fixed** — Use named symbols everywhere
- **fixed** — Don't run teardown effects when deriveds are unfreezed
- **fixed** — Unset context synchronously in run

###### Patch Changes

-   fix(print): handle `svelte:body` and fix keyframe percentage double-printing ([#18234](https://github.com/sveltejs/svelte/pull/18234))

-   fix: execute uninitialized derived even if it's destroyed ([#18228](https://github.com/sveltejs/svelte/pull/18228))

-   fix: use named symbols everywhere ([#18238](https://github.com/sveltejs/svelte/pull/18238))

-   fix: don't run teardown effects when deriveds are unfreezed ([#18227](https://github.com/sveltejs/svelte/pull/18227))

-   fix: unset context synchronously in `run` ([#18236](https://github.com/sveltejs/svelte/pull/18236))

### 5.55.7

- Date: 2026-05-14
- Version: 5.55.7
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.7
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.55.7

- **security** — Prevent XSS on hydratable from user contents
- **security** — Disallow empty attribute names during SSR
- **security** — Harden regex
- **fixed** — Move Svelte runtime properties to symbols

###### Patch Changes

-   fix: prevent XSS on `hydratable` from user contents ([`a16ebc67bbcf8f708360195687e1b2719463e1a4`](https://github.com/sveltejs/svelte/commit/a16ebc67bbcf8f708360195687e1b2719463e1a4))

-   chore: bump devalue ([#18219](https://github.com/sveltejs/svelte/pull/18219))

-   fix: disallow empty attribute names during SSR ([`547853e2406a2147ad7fb5ffeba95b01bd9642da`](https://github.com/sveltejs/svelte/commit/547853e2406a2147ad7fb5ffeba95b01bd9642da))

-   fix: harden regex ([`d2375e2ebcab5c88feb5652f1a9d621b8f06b259`](https://github.com/sveltejs/svelte/commit/d2375e2ebcab5c88feb5652f1a9d621b8f06b259))

-   fix: move Svelte runtime properties to symbols ([`e1cbbd96441e82c9eb8a23a2903c0d06d3cda991`](https://github.com/sveltejs/svelte/commit/e1cbbd96441e82c9eb8a23a2903c0d06d3cda991))

### 5.55.6

- Date: 2026-05-14
- Version: 5.55.6
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.6
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.55.6

- **fixed** — Leave stale promises to wait for a later resolution, instead of rejecting
- **fixed** — Keep dependencies of $state.eager/pending
- **fixed** — Reapply context after transforming error during SSR
- **fixed** — Don't rebase just-created batches
- **changed** — Allow null for pending in typings
- **fixed** — Flush eager effects in production
- **fixed** — Rethrow error of failed iterable after calling return()
- **fixed** — Account for proxified instance when updating bind:this
- **fixed** — Ensure scheduled batch is flushed if not obsolete
- **fixed** — Resolve stale deriveds with latest value
- **fixed** — Correctly compile component member expressions for SSR
- **fixed** — Reset source.updated stack traces after flush
- **fixed** — Replace async blocking strategy with merging
- **fixed** — Allow @debug tags to reference awaited variables
- **fixed** — Re-run fallback props if dependencies update
- **fixed** — Abort running obsolete async branches
- **fixed** — Ignore comments when reading CSS values
- **fixed** — Wrap Promise.all in save during SSR
- **fixed** — Ignore false-positive errors of $inspect dependencies

###### Patch Changes

-   fix: leave stale promises to wait for a later resolution, instead of rejecting ([#18180](https://github.com/sveltejs/svelte/pull/18180))

-   fix: keep dependencies of `$state.eager/pending` ([#18218](https://github.com/sveltejs/svelte/pull/18218))

-   fix: reapply context after transforming error during SSR ([#18099](https://github.com/sveltejs/svelte/pull/18099))

-   fix: don't rebase just-created batches ([#18117](https://github.com/sveltejs/svelte/pull/18117))

-   chore: allow `null` for `pending` in typings ([#18201](https://github.com/sveltejs/svelte/pull/18201))

-   fix: flush eager effects in production ([#18107](https://github.com/sveltejs/svelte/pull/18107))

-   fix: rethrow error of failed iterable after calling `return()` ([#18169](https://github.com/sveltejs/svelte/pull/18169))

-   fix: account for proxified instance when updating `bind:this` ([#18147](https://github.com/sveltejs/svelte/pull/18147))

-   fix: ensure scheduled batch is flushed if not obsolete ([#18131](https://github.com/sveltejs/svelte/pull/18131))

-   fix: resolve stale deriveds with latest value ([#18167](https://github.com/sveltejs/svelte/pull/18167))

-   chore: remove unnecessary `increment_pending` calls ([#18183](https://github.com/sveltejs/svelte/pull/18183))

-   fix: correctly compile component member expressions for SSR ([#18192](https://github.com/sveltejs/svelte/pull/18192))

-   fix: reset `source.updated` stack traces after `flush` ([#18196](https://github.com/sveltejs/svelte/pull/18196))

-   fix: replacing async 'blocking' strategy with 'merging' ([#18205](https://github.com/sveltejs/svelte/pull/18205))

-   fix: allow `@debug` tags to reference awaited variables ([#18138](https://github.com/sveltejs/svelte/pull/18138))

-   fix: re-run fallback props if dependencies update ([#18146](https://github.com/sveltejs/svelte/pull/18146))

-   fix: abort running obsolete async branches ([#18118](https://github.com/sveltejs/svelte/pull/18118))

-   fix: ignore comments when reading CSS values ([#18153](https://github.com/sveltejs/svelte/pull/18153))

-   fix: wrap `Promise.all` in `save` during SSR ([#18178](https://github.com/sveltejs/svelte/pull/18178))

-   fix: ignore false-positive errors of `$inspect` dependencies ([#18106](https://github.com/sveltejs/svelte/pull/18106))

### 5.55.5

- Date: 2026-04-23
- Version: 5.55.5
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.5
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.55.5

- **fixed** — don't mark deriveds while an effect is updating
- **fixed** — do not dispatch introstart event with animation of animate directive

###### Patch Changes

-   fix: don't mark deriveds while an effect is updating ([#18124](https://github.com/sveltejs/svelte/pull/18124))

-   fix: do not dispatch introstart event with animation of animate directive ([#18122](https://github.com/sveltejs/svelte/pull/18122))

### 5.55.4

- Date: 2026-04-14
- Version: 5.55.4
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.4
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.55.4

- **fixed** — Never mark a child effect root as inert
- **fixed** — Reset context after waiting on blockers of @const expressions
- **fixed** — Keep flushing new eager effects

###### Patch Changes

-   fix: never mark a child effect root as inert ([#18111](https://github.com/sveltejs/svelte/pull/18111))

-   fix: reset context after waiting on blockers of `@const` expressions ([#18100](https://github.com/sveltejs/svelte/pull/18100))

-   fix: keep flushing new eager effects ([#18102](https://github.com/sveltejs/svelte/pull/18102))

### 5.55.3

- Date: 2026-04-10
- Version: 5.55.3
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.3
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.55.3

- **fixed** — ensure proper HMR updates for dynamic components
- **fixed** — correctly calculate @const blockers
- **fixed** — freeze deriveds once their containing effects are destroyed
- **fixed** — defer error boundary rendering in forks
- **fixed** — avoid false positives for reactivity loss warning

###### Patch Changes

-   fix: ensure proper HMR updates for dynamic components ([#18079](https://github.com/sveltejs/svelte/pull/18079))

-   fix: correctly calculate `@const` blockers ([#18039](https://github.com/sveltejs/svelte/pull/18039))

-   fix: freeze deriveds once their containing effects are destroyed ([#17921](https://github.com/sveltejs/svelte/pull/17921))

-   fix: defer error boundary rendering in forks ([#18076](https://github.com/sveltejs/svelte/pull/18076))

-   fix: avoid false positives for reactivity loss warning ([#18088](https://github.com/sveltejs/svelte/pull/18088))

### 5.55.2

- Date: 2026-04-07
- Version: 5.55.2
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.2
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.55.2

- **fixed** — Invalidate @const tags based on visible references in legacy mode
- **fixed** — Handle parens in template expressions more robustly
- **fixed** — Disallow -- in idPrefix
- **fixed** — Correct types for ontoggle on <details> elements
- **fixed** — Don't override $destroy/set/on instance methods in dev mode
- **fixed** — Unskip branches of earlier batches after commit
- **fixed** — Never set derived.v inside fork
- **fixed** — Skip rebase logic in non-async mode
- **fixed** — Don't reset status of uninitialized deriveds

###### Patch Changes

-   fix: invalidate `@const` tags based on visible references in legacy mode ([#18041](https://github.com/sveltejs/svelte/pull/18041))

-   fix: handle parens in template expressions more robustly ([#18075](https://github.com/sveltejs/svelte/pull/18075))

-   fix: disallow `--` in `idPrefix` ([#18038](https://github.com/sveltejs/svelte/pull/18038))

-   fix: correct types for `ontoggle` on `<details>` elements ([#18063](https://github.com/sveltejs/svelte/pull/18063))

-   fix: don't override `$destroy/set/on` instance methods in dev mode ([#18034](https://github.com/sveltejs/svelte/pull/18034))

-   fix: unskip branches of earlier batches after commit ([#18048](https://github.com/sveltejs/svelte/pull/18048))

-   fix: never set derived.v inside fork ([#18037](https://github.com/sveltejs/svelte/pull/18037))

-   fix: skip rebase logic in non-async mode ([#18040](https://github.com/sveltejs/svelte/pull/18040))

-   fix: don't reset status of uninitialized deriveds ([#18054](https://github.com/sveltejs/svelte/pull/18054))

### 5.55.1

- Date: 2026-03-29
- Version: 5.55.1
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.1
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.55.1

- **fixed** — correctly handle bindings on the server
- **fixed** — prevent hydration error on async {@html ...}
- **fixed** — cleanup superTypeParameters in ClassDeclarations/ClassExpression
- **fixed** — improve duplicate module import error message
- **fixed** — reschedule new effects in prior batches

###### Patch Changes

-   fix: correctly handle bindings on the server ([#18009](https://github.com/sveltejs/svelte/pull/18009))

-   fix: prevent hydration error on async `{@html ...}` ([#17999](https://github.com/sveltejs/svelte/pull/17999))

-   fix: cleanup `superTypeParameters` in `ClassDeclarations`/`ClassExpression` ([#18015](https://github.com/sveltejs/svelte/pull/18015))

-   fix: improve duplicate module import error message ([#18016](https://github.com/sveltejs/svelte/pull/18016))

-   fix: reschedule new effects in prior batches ([#18021](https://github.com/sveltejs/svelte/pull/18021))

### 5.55.0

- Date: 2026-03-23
- Version: 5.55.0
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.55.0
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.55.0

- **added** — Export TweenOptions, SpringOptions, SpringUpdateOptions and Updater from svelte/motion
- **fixed** — Ensure HMR wrapper forwards correct start/end nodes to active effect

###### Minor Changes

-   feat: export TweenOptions, SpringOptions, SpringUpdateOptions and Updater from svelte/motion ([#17967](https://github.com/sveltejs/svelte/pull/17967))

###### Patch Changes

-   fix: ensure HMR wrapper forwards correct start/end nodes to active effect ([#17985](https://github.com/sveltejs/svelte/pull/17985))

### 5.54.1

- Date: 2026-03-21
- Version: 5.54.1
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.54.1
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.54.1

- **fixed** — hydration comments during hmr
- **fixed** — null out effect.b in destroy_effect
- **fixed** — group sync statements
- **fixed** — defer batch resolution until earlier intersecting batches have committed
- **fixed** — properly invoke iterator.return() during reactivity loss check
- **fixed** — remove trailing semicolon from {@const} tag printer

###### Patch Changes

-   fix: hydration comments during hmr ([#17975](https://github.com/sveltejs/svelte/pull/17975))

-   fix: null out `effect.b` in `destroy_effect` ([#17980](https://github.com/sveltejs/svelte/pull/17980))

-   fix: group sync statements ([#17977](https://github.com/sveltejs/svelte/pull/17977))

-   fix: defer batch resolution until earlier intersecting batches have committed ([#17162](https://github.com/sveltejs/svelte/pull/17162))

-   fix: properly invoke `iterator.return()` during reactivity loss check ([#17966](https://github.com/sveltejs/svelte/pull/17966))

-   fix: remove trailing semicolon from {@const} tag printer ([#17962](https://github.com/sveltejs/svelte/pull/17962))

### 5.54.0

- Date: 2026-03-17
- Version: 5.54.0
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.54.0
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.54.0

- **added** — Allow `css`, `runes`, `customElement` compiler options to be functions
- **fixed** — Reinstate reactivity loss tracking

###### Minor Changes

-   feat: allow `css`, `runes`, `customElement` compiler options to be functions ([#17951](https://github.com/sveltejs/svelte/pull/17951))

###### Patch Changes

-   fix: reinstate reactivity loss tracking ([#17801](https://github.com/sveltejs/svelte/pull/17801))

### 5.53.13

- Date: 2026-03-17
- Version: 5.53.13
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.53.13
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.53.13

- **fixed** — Ensure $inspect after top level await doesn't break builds
- **fixed** — Resume inert effects when they come from offscreen
- **fixed** — Don't eagerly access not-yet-initialized functions in template
- **fixed** — Discard batches made obsolete by commit
- **fixed** — Ensure 'is standalone child' is correctly reset
- **fixed** — Remove nodes in boundary when work is pending and HMR is active

###### Patch Changes

-   fix: ensure `$inspect` after top level await doesn't break builds ([#17943](https://github.com/sveltejs/svelte/pull/17943))

-   fix: resume inert effects when they come from offscreen ([#17942](https://github.com/sveltejs/svelte/pull/17942))

-   fix: don't eagerly access not-yet-initialized functions in template ([#17938](https://github.com/sveltejs/svelte/pull/17938))

-   fix: discard batches made obsolete by commit ([#17934](https://github.com/sveltejs/svelte/pull/17934))

-   fix: ensure "is standalone child" is correctly reset ([#17944](https://github.com/sveltejs/svelte/pull/17944))

-   fix: remove nodes in boundary when work is pending and HMR is active ([#17932](https://github.com/sveltejs/svelte/pull/17932))

### 5.53.12

- Date: 2026-03-14
- Version: 5.53.12
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.53.12
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.53.12

- **fixed** — update `select.__value` on `change` event
- **added** — add `invariant` helper for debugging
- **fixed** — ensure derived values are correct across batches
- **fixed** — handle async RHS in `assignment_value_stale`
- **fixed** — avoid traversing clean roots

###### Patch Changes

-   fix: update `select.__value` on `change` ([#17745](https://github.com/sveltejs/svelte/pull/17745))

-   chore: add `invariant` helper for debugging ([#17929](https://github.com/sveltejs/svelte/pull/17929))

-   fix: ensure deriveds values are correct across batches ([#17917](https://github.com/sveltejs/svelte/pull/17917))

-   fix: handle async RHS in `assignment_value_stale` ([#17925](https://github.com/sveltejs/svelte/pull/17925))

-   fix: avoid traversing clean roots ([#17928](https://github.com/sveltejs/svelte/pull/17928))

### 5.53.11

- Date: 2026-03-12
- Version: 5.53.11
- Original notes: https://github.com/sveltejs/svelte/releases/tag/svelte%405.53.11
- Permalink: https://whatsnew.fyi/product/svelte/releases/5.53.11

- **fixed** — Remove untrack circular dependency
- **fixed** — Recover from errors that leave a corrupted effect tree
- **fixed** — Properly lazily evaluate RHS when checking for assignment_value_stale
- **fixed** — Resolve boundary in correct batch when hydrating
- **changed** — Rebase batches after process, not during

###### Patch Changes

-   fix: remove `untrack` circular dependency ([#17910](https://github.com/sveltejs/svelte/pull/17910))

-   fix: recover from errors that leave a corrupted effect tree ([#17888](https://github.com/sveltejs/svelte/pull/17888))

-   fix: properly lazily evaluate RHS when checking for `assignment_value_stale` ([#17906](https://github.com/sveltejs/svelte/pull/17906))

-   fix: resolve boundary in correct batch when hydrating ([#17914](https://github.com/sveltejs/svelte/pull/17914))

-   chore: rebase batches after process, not during ([#17900](https://github.com/sveltejs/svelte/pull/17900))