Learn Kotlin for free
Modern JVM language. Concise, null-safe, batteries included. On Libre Academy you learn Kotlin for free by writing real code in an in-editor workbench, graded by hidden tests — desktop app (native toolchain). No paywall, no sign-up.
Kotlin courses
- Kotlin Challenges — Kotlin · 46 lessons
- Exercism Kotlin Track — Kotlin · 88 lessons
- Kotlin Koans — Kotlin · 43 lessons