What is a good way to handle new additions to Alexandria that are not fully fledged out yet? As Hans noticed himself over this week, it usually takes an incredible amount of time and effort to come up with something with complete semantics. Time is a scarce resource, and even if it was not, only experience and actual usage will discover edges cases. Common Lisp itself has been tried out and implemented many times during the standardization process itself which is one of the reasons it's engineered as well as it is. What about providing an :ALEXANDRIA.EXPERIMENTAL package that uses :ALEXANDRIA? New additions go into the experimental package which is advertised not necessarily to be fully backwards compatible. People can explicitly :IMPORT-FROM that package (which will continue to work even when the symbol moves from there into :ALEXANDRIA, assuming no incompatible changes have been made.) T