How can I write my own plugin for jupyverse?

Question

I learned how to create my own plugins for adding new endpoints (thanks to KenKi0). But now I want to write a plugin that would perform a certain action when the kernel finishes working for one cell. An event for me is a message that is processed in the fps_kernels plugin.

How can I write my own plugin?

I tried to inherit from the _Kernels from fps_kernels and override one method, but when starting, jupyverse gives an error, because it sees duplicate endpoints, because, by the url, my plugin also sets the parent kernel object hook.

Maybe there is a way to have some callbacks or hooks in the standard plugin to subscribe to events and handle them in my plugin?