As I mentioned before, I am making small abstraction FW.
For giving the task a vista, I want to make a list of the requirements in advance.

• Abstract Model (I hope the ActiveORM will be)
• Basic HTML tag helpers (such as "tag", "url_for")
• Starting up hook to modify others
• Way to register helpers
• Way to read/write configuration of plugin

In particular, abstract model is quite important.
There are already several efforts, but they all are probably not succeeding.
I think the reason of the failure is what most of them had been concentrating to make abstraction of models for models.
It must be designed for agnostic plugins.

Suppose you are an application developer and you are writing some code.
Obviously, the FW and ORM have already been chosen.
So you have no need to treat various ORMs for making the app.
Only agnostic plugins need the abstract model.

What is the requirements of the plugins?

• read_many with options for specifying :limit and :offset
• read_one, create, destroy, update
• read/write access to attributes
• counting, searching, association and so on.

Is it the DataMapper?
Yeah, it is nearly equals to. But it must have more flexibility.

In conclusion, we should not make an abstraction of models but an abstraction of plugin's requirements to FW.