Kotlin Tutorial #21: Kotlin DSLs — Writing Expressive APIs

In the previous tutorial, you learned about inline functions and reified types. Now let’s learn about DSLs. A DSL (Domain-Specific Language) is a small language designed for a specific task. Kotlin makes it easy to create DSLs using lambdas with receivers. In this tutorial, you will learn: Lambdas with receiver Building a config DSL Nested DSL builders @DslMarker annotation HTML builder DSL Route DSL Query builder DSL Gradle-style DSL What is a DSL? A DSL is a language designed for a specific domain. You already use Kotlin DSLs every day: ...

March 22, 2026 · 9 min