Here is a (not comprehensive) list of my open-source projects:

• RESTwars: An online game (like the good old browsergames) which can be played via a REST interface.
• RESTwars Kotlin: RESTwars implemented in Kotlin.
• Heimdall: This library implements a secure and upgradeable password hashing mechanism.
• Argon2-JVM: A JVM binding for Argon2.
• VhdCompact: Small tool to compact VHD images.
• Kotlin-One-EPUB: Kotlin documentation in EPUB format for eBook-readers.
• SonarQube build breaker: Tool (or maven plugin) to break your CI build if the SonarQube quality gate turns red.
• Mr. Canary: A TCP reverse proxy with canaries built in.

If you are interested in more projects, check out my GitHub repositories.