This is the fifty-sixth release in the Cats Effect 3.x lineage. It is fully binary compatible with every 3.x release and fully source-compatible with the 3.6.x lineage. Please note that we did break binary compatibility with 3.6.0 RC1 (not with 3.5.x) in order to fix some things, so if you published anything against that release you will need to reconsider your life choices.

[!WARNING] Please note that Cats Effect 3.6.x is targeting Scala Native 0.4.x, which means it does not at present support native multithreading. This was a very intentional choice meant to give us an opportunity to break binary compatibility only on Scala Native if necessary when upgrading to Scala Native 0.5 and as we discover the impacts of the integrated runtime on the downstream ecosystem. It also reduces risk since Native multithreading in the runtime is a significant lift and we want to make sure we isolate that change from the already significant changes in 3.6.0. This functionality has already merged into the development branch and we plan to release it in 3.7.0 as soon as possible.

What's Changed

Bug Fixes

• Also interrupt pollers when shutting down the WSTP by @durban in https://github.com/typelevel/cats-effect/pull/4340
• Make deprecated IO.onError package private by @CJSmith-0141 in https://github.com/typelevel/cats-effect/pull/4343

Documentation

• Document PollingSystem#metrics by @antoniojimeneznieto in https://github.com/typelevel/cats-effect/pull/4334

Behind the Scenes

• Update versions for 3.6.0 by @djspiewak in https://github.com/typelevel/cats-effect/pull/4311
• Restore GraalVM Native Image test in CI by @armanbilge in https://github.com/typelevel/cats-effect/pull/4315

New Contributors

• @CJSmith-0141 made their first contribution in https://github.com/typelevel/cats-effect/pull/4343

Full Changelog: https://github.com/typelevel/cats-effect/compare/v3.6.0...v3.6.1