Currently swank-compilation-result is declared as: (defstruct (:swank-compilation-result (:type list) :named (:conc-name swank-compilation-result.) (:constructor make-swank-compilation-result ())) notes ; results ; one result is of type (MEMBER T NIL :COMPLAINED) durations ; ) All the slots are lists. Can we change that, so that one compilation-result contains only one element of those lists? If a command runs multiple compilations it could return a list of those simpler compilation-results. Helmut.