You can define your own custom steps and seamlessly make them of the CPG query language, using Scala’s enrich my library pattern. E.g. let’s say you want to define a step publicExampleOrg on method:

implicit class MyMethodTraversals(method: Traversal[Method]) {
  def publicExampleOrg = method.fullName(".*org.example.*").isPublic
}

To try it out, you can just paste this into the Joern REPL. Usage: cpg.method.publicExampleOrg

Note: tab completion works, i.e. if you type cpg.method.pu<TAB> it will auto-complete.