Kotlin Symbol Processing API

Welcome to KSP!

Kotlin Symbol Processing (KSP) is an API that you can use to develop lightweight compiler plugins. KSP provides a simplified compiler plugin API that leverages the power of Kotlin while keeping the learning curve at a minimum. Compared to KAPT, annotation processors that use KSP can run up to 2x faster.

Most of the documentation of KSP can be found on kotlinlang.org. Here are some handy links:

• Overview
• Quickstart
• Libraries that support KSP
• Why KSP?
• Examples
• How KSP models Kotlin code
• Reference for Java annotation processor authors
• Incremental processing notes
• Multiple round processing notes
• KSP on multiplatform projects
• Running KSP from command line
• FAQ

Feedback and Bug Reporting

Please let us know what you think about KSP by filing a Github issue or connecting with our team in the #ksp channel in the Kotlin Slack workspace!

If you are interested in sending PRs, please also check out the Contributor guide.

Ongoing and Future Works

Here are some planned features that have not yet been completely implemented:

• Support new Kotlin compiler
• Improve support to multiplatform. E.g., running KSP on a subset of targets / sharing computations between targets
• Improve performance. There a bunch of optimizations to be done!
• Make the IDE aware of the generated code
• Keep fixing bugs!