Подробный список изменений в Котлин 1.5.0, с ссылками на документацию, статьи и видео

- Stable language features – JVM records, sealed interfaces, and inline classes.
- Standard and test library improvements, including stable unsigned integer types, extensions for java.nio.file.Path, as well as String, Char, and Duration API improvements.
- Kotlin/JVM improvements, including the new default JVM IR compiler.
- Kotlin/Native improvements, including faster debug compilation for Linux and iOS applications.
- Kotlin/JS improvements, including migration of more JS libraries to the new Kotlin/JS IR compiler.

#kotlin

https://blog.jetbrains.com/kotlin/2021/05/kotlin-1-5-0-released/