NixOS declarative configuration for Neo4j with predefined plugins

Hello.

I am trying to create my own portable configuration for NixOS now. That is very conveniently, but sometimes you want more. Don't you?

Have anyone any idea how to declare config in *.nix file to install Neo4j with predefined set of plugins?
I can set home (and data, plugins etc) directory, can extend configuration and such. But how to load plugins JARs with nixos-rebuild? And maybe even create the initial database and run Cypher script in it?

I will be really appreciated for any ideas and examples. It will be great to get it working as expected on any machine "out of the box".
Thank you.