Hi! Every time I read "asdf", I feel a pain. I've read that there is an attempt to gain resources to improve asdf. I have a sort of plan.
1. Shims. Recent tightening of rules for system definitions is ok, but there are old systems with no maintainers. If such system does not obey the rules, one can introduce "shim" concept. I've met them in JS culture where they serve as third-party adapters to connect two mismatching things. In the simplest way shim is just an alternative directory hierarchy with shim asd files, isomorphic to local lisp directory structure. When looking for system, asdf must search in shims directory first, and only then in the directory of the file itself. Also things like quicklisp might take care of installing shims where they exist. Maintanence of shims for all popular systems can be done within a separate git repository. 2. Get rid of upgrade. Upgrade feature requires to maintain a 3d array of possible cases, where dimensions are "old asdf version", "new asdf version" and "lisp implementation". It is hard to maintain and it will get harder and harder to maintain as the time goes on. Also upgrade is a good test of CLOS, but running tests at the very beginning of image bootstrap is not a good idea because there is no e.g. SLIME to work with convenience. 3. Last, but most important actually. Prioritize manual, FAQ, Wiki and all like this. Instead, when loading asdf, allow the user to pass the parameter that fills asdf database with the initial loaded system information. It would be also good to have an utility to extract this database from some old asdf versions. This way we have a slight chance to make things easier, upgrade process explicit and under user's control.