Well, the point is not to replace metacello but to go towards a per package metadata description allowing some flexibility with the introduction of virtual packages.
This will allow, in a first time, to set up a package repository and more important, a web site on top of it. In a second time, I also want to enable more flexibility in expressing dependencies constraints (eg. > 2.0, 3.*, etc.). To achieve that, you need a very performant dependency solver and I would like to reuse linux ones (it has be done for ocaml by example) through CUDF (check http://mancoosi.org/).

For now, I implemented a simple solver for static dependency constraints (=1.2). I checked Metacello implementation and it looked to me that approaches are a bit too far to be able to reuse the whole code. For sure, it is not as robust as Metacello is, because you enhanced it for years.
What I want now, is to experiment (let's name it) Cargo Package Manager to see if it fits the needs. Pharo bootstrap is the first use case.


What I would like, is that, at the end, the dependency solver get out of Pharo and that we use already existing linux ones. What will stay into Pharo are packages metadata and the way to load a list of packages.