Ktor

Judgement

What it is

Framework or platform

What it does

JetBrains' asynchronous Kotlin framework for building web servers, microservices and HTTP clients using coroutines, with pluggable features.

Adopt it when

Your team writes Kotlin and wants a lightweight, coroutine-based server or a multiplatform HTTP client.

Watch out

Less batteries-included than Spring Boot, so you assemble more yourself.

Ready for

Production-ready

Runs as

Library

Built with

Kotlin and Netty

How established

Established: started 11 years ago, latest release 3.6.1.

What the license allows

You can build it into a product you sell, as long as you keep its copyright notice.

Judged on 2026-11-03 from the project's README and GitHub data. The license and age lines are worked out directly.

Built from

Follow it down: Ktor → Kotlin → JDK → LLVM project → runs on a microchip

How compilers were built, back to punched paper tape

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