Getting java.lang.NoClassDefFoundError: io/gatling/core/cli/GatlingOptionParser when upgrading to 3.11.3

Gatling version: 3.11.2 (must be up to date)
Gatling flavor: [ 3.11.3] java [11 ] kotlin [karate-gatling=1.4.1 ] scala [2.13.14]
Gatling build tool: [ maven] maven gradle sbt bundle

Adding exception here:

at java.base/java.lang.reflect.Method.invoke(
at io.gatling.plugin.util.ForkMain.runMain(
at io.gatling.plugin.util.ForkMain.main(
Caused by: java.lang.NoClassDefFoundError: io/gatling/core/cli/GatlingOptionParser


I am not referring to this class from my code. I am assuming it would be referred by one of the libraries I am using… I can see GatlingOptionParser class does not exist in latest version. Can you tell why and where is it still referred ?

You’re most likely mixing Gatling libraries with different versions. You should be using 3.11.3 for all the Gatling libraries in your classpath.

Note: karate-gatling is not supported here. Please use genuine Gatling for load testing as the performance of this third party is really suboptimal.