Important: This news article covers an old version of Javalin (v4.4.0). The current version is v6.1.3.
See the documentation page for up-to-date information.

New features

  • The Javalin Cookie class now has a lot more constructors when used from Java
  • The Context#seekableStream method now supports files larger than 2GB.


  • The SseHandler now sets "X-Accel-Buffering" to no, preventing buffering
  • All Java context resolvers are now JVM fields
  • File descriptors are now closed in JavalinVue#walkPaths
  • Trying to access a session attribute no longer creates a new session
  • JPG is now an alias to JPEG for mime types
  • Uploads will now be cached to disk from the first byte


  • Kotlin, Jetty, Jackson, and SLF4J have all been bumped to their latest versions