This gem contains things related to the datamill gem which have not proven to be useful or stable enough to go into the main gem.
Recall these datamill concepts first:
A "behaviour" is an implementation of how cells of a certain kind need to be
operated. For Datamill, a Behaviour is just an object that implements the
Datamill::Cell::Behaviour interface.
Behaviours implement functions managing the cell's State, which
encapsulates all the state of and information about the cell, and contains no behaviour
of itself. The behaviour functions themselves are stateless.
This is a rather functional approach and not always nice to operate with.
To give this a more object-oriented flavour,
you can implement a cell culture using Datamill::Extra::CellCulture.
A cell culture provides the behaviour object, the interface toward the reactor, for you. Inside the cell culture you describe what a cell run looks like, a class instantiated by the behaviour to handle a single invocation for the cell. On this cell run you can implement general handling around all method calls (like logging, exception handling, presenting a cell's id in a more suitable way...) as well as respond to cell messages.
Model events allow for hooking into the lifecycle events of classic ORMs
to emit Events. These events are managed by corresponding Datamill::Event subclasses.