# Scala 3.9.0-RC4

- Product: Scala (https://whatsnew.fyi/product/scala)
- Vendor: Scala Center
- Date: 2026-07-23
- Version: 3.9.0-RC4
- Original notes: https://github.com/scala/scala3/releases/tag/3.9.0-RC4
- Permalink: https://whatsnew.fyi/product/scala/releases/3.9.0-rc4
- Labels: Pre-release

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.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **fixed** — Fix generic signatures for inherited inner classes
- **fixed** — Fix regression in generic signatures of mixed-in trait setters
- **fixed** — Fix regression by reverting isPrimitiveValueType change
- **fixed** — Skip unresolved annotation trees during TASTy loading

#### Backported changes

- Fix generic signatures for inherited inner classes [#26549](https://github.com/scala/scala3/pull/26549)
- Fix regression #26374: generic signatures of mixed-in trait setters [#26542](https://github.com/scala/scala3/pull/26542)
- Fix regression #26550: revert isPrimitiveValueType change [#26565](https://github.com/scala/scala3/pull/26565)
- Skip unresolved annotation trees (during TASTy loading) [#26520](https://github.com/scala/scala3/pull/26520)



#### Contributors

Thank you to all the contributors who made this release possible 🎉

According to `git shortlog -sn --no-merges 3.9.0-RC3..3.9.0-RC4` these are:

```
     4  Rikito Taniguchi
     2  Wojciech Mazur
```