JetBrains Releases Ktor 3.6.0 with HTTP/3 & OpenID Connect Support

On September 18, 2026, JetBrains unveiled Ktor 3.6.0, a significant update to the open-source Kotlin web framework. This release brings experimental HTTP/3 support via the Netty engine, enhancing performance on unreliable networks. A type-safe OpenID Connect authentication module simplifies integration with OIDC providers, cutting down on boilerplate code and runtime errors.

The framework also sees routing enhancements with a cleaner DSL syntax and automatic handling of trailing slashes, making route definitions more readable. The client library now comes with sensible defaults for JVM, JavaScript, and native platforms, reducing setup time for cross-platform projects. Quality-of-life improvements include better asynchronous DNS resolution for the CIO engine, fixes for duplicate cookie parsing, and JavaScript fetch() overrides.

Simon Vergauwen, lead maintainer of Ktor, highlighted that this release represents a leap forward for the Kotlin ecosystem, providing developers with the tools needed to build secure, high-performance services effortlessly. Ktor's embrace of HTTP/3 and first-class OpenID Connect support addresses common pain points, such as integrating modern protocols and authentication flows.

The new version promises to streamline modern API development, aligning Kotlin with the industry's push toward QUIC and enhancing its appeal for building cloud-native APIs. With the next 4.0 release expected in early 2027, JetBrains continues to refine Ktor, focusing on full HTTP/3 stability, deeper coroutine integration, and expanded serverless platform support.