ElasticSearch Plugins with its own thread pool

In a custom script plugin, is it possible to have its thread pool for some concurrency? For example: in this execute method, can I do some concurrency using a thread pool?

What I understand is that the script plugin will get called in some search threadpool, but can I have another one inside the plugin for more concurrency? I see this method getExecutorBuilders, but not able to understand how it is used.