Kotlinach

Kotlinach is a fictional programming language created to explore language extension ideas within the Kotlin ecosystem. Designed to interoperate with Kotlin while offering a more concise syntax and enhanced support for domain-specific languages, it targets the JVM and JavaScript runtimes and emphasizes predictable performance and a strong static type system.

Its design combines a statically-typed core with type inference, null safety, and pattern matching. It supports coroutine-like asynchronous primitives, lightweight DSL builders, and first-class blocks that can be embedded in host Kotlin code. A dedicated interop mechanism enables calling Kotlin libraries from Kotlinach and exposing Kotlinach APIs to Kotlin without heavy wrappers.

The concept emerged in community discussions among Kotlin researchers and educators in the late 2010s. While it has inspired experimentation and teaching demonstrations, Kotlinach is not an official language. Development progress remains modest, and IDE support exists only in a set of experimental plugins. It is primarily used for illustrating DSL design and language concepts rather than for production systems.

In practice, Kotlinach is used for exploring domain-specific configuration languages, data transformation pipelines, and teaching language design within Kotlin projects. It functions as a case study and learning tool rather than a broadly adopted programming option.

See also: Kotlin (programming language), Kotlin/JS, domain-specific language, DSL, coroutine.