I am actually in the process of writing a zephir mashup of the phalcon db/model code with Spot
https://github.com/vlucas/Spot
https://github.com/brandonlamb/Spot
Spot is a great PHP datamapper, I have used it and really like for its simplicity and lack of bloat. I ended up forking and adding a bunch. I came across this after using Idiorm/Paris which lead to a custom rewrite of those libraries and finally discovered the data mapper pattern (I totally favor over active record).
By forking Spot, I re-tooled a lot, added a db2 adapter, added join support and whatnot for query builder.
Now I am taking phalcons zephir db code as a base, stripping out stuff like migration (just my opinion this is bloat) and mashing in Spot's code and converting to more datamapper pattern.
I just started a new repository this weekend, didnt get too far along yet. my vision is to have a very minimalist codebase, so nothing like createTable, addIndex or any of that schema/table/index manipulation. Really just get it down to a datamapper for CRUD operations.