Scala 2.12.21 release notes (DRAFT)

2.12.21.md

@@ -0,0 +1,50 @@
+# Scala 2.12.21 (DRAFT)
+
+The Scala team at Akka is pleased to announce Scala 2.12.21.
+
+This release is compatible with JDK 25 LTS and also introduces preliminary support for JDK 26.
+
+The following are highlights of this release:
+
+### JDK 25 and 26 support
+
+- Compiling on JDK 25 is now supported [#11028](https://github.com/scala/scala/pull/11028)
+- Compiling on JDK 26 is also supported [#11172](https://github.com/scala/scala/pull/11172)
+  - Note: compilation of `Ordering` subclasses (overriding `min` / `max`) may fail on Java 26, see [comment on #11175](https://github.com/scala/scala/pull/11175#issuecomment-3542497701)
+
+### New `@uncheckedOverride` annotation
+
+The new `@uncheckedOverride` annotation is equivalent to the `override` keyword, except that it allows to override nothing. This is useful when cross-building: a method may override or not, depending on the version of some dependency. [#11175](https://github.com/scala/scala/pull/11175)
+
+### GPG key change
+
+This release is signed with a different GPG key than previous Scala 2.12 releases. The new key is the same one used by Scala 3. [#11158](https://github.com/scala/scala-dev/issues/918)
+
+### More changes
+
+For the complete 2.12.21 change lists, see [all merged PRs](https://github.com/scala/scala/pulls?q=is%3Amerged+-label%3Ainternal+milestone%3A2.12.21) and [all closed bugs](https://github.com/scala/bug/issues?utf8=%E2%9C%93&q=is%3Aclosed+milestone%3A2.12.21).
+
+## Compatibility
+
+As usual for our minor releases, Scala 2.12.21 is [binary-compatible](https://docs.scala-lang.org/overviews/core/binary-compatibility-of-scala-releases.html) with the whole Scala 2.12 series.
+
+## Contributors
+
+A big thank you to everyone who's helped improve Scala by reporting bugs, improving our documentation, spreading kindness in discussions around Scala, and submitting and reviewing pull requests! You are all magnificent.
+
+This release was brought to you by 9 contributors, according to `git shortlog -sn --no-merges @ ^v2.12.20`. Thank you Seth Tisue, Lukas Rytz, A. P. Marki, Friendseeker, Matthias Kurz, NthPortal, Philippus Baalman, Scala Steward, dependabot[bot].
+
+Thanks to [Akka](https://akka.io) for their continued sponsorship of the Scala 2 team’s efforts. Akka offers commercial support for Scala.
+
+## Scala 2.12 notes
+
+The [release notes for Scala 2.12.0](https://github.com/scala/scala/releases/v2.12.0) have important information applicable to the whole 2.12 series.
+
+## Obtaining Scala
+
+Scala releases are available through a variety of channels, including (but not limited to):
+
+* Bump the `using scala` setting in your Scala-CLI project
+* Bump the `scalaVersion` setting in your sbt or Mill project
+* Download a distribution from [scala-lang.org](https://scala-lang.org/download/2.12.21.html)
+* Obtain JARs via [Maven Central](https://search.maven.org/search?q=g:org.scala-lang%20AND%20v:2.12.21)