If using an IDE, then IntelliJ is the bomb-diggaty...

# server

[Gregg]

If using an IDE, then IntelliJ is the bomb-diggaty, especially for Kotlin. That said, you can do with notepad or vi. The simplest Spring way to use Kotlin is this: https://spring.io/blog/2016/02/15/developing-spring-boot-applications-with-kotlin