+ He has fixed various bugs, and also done a lot of internal
+ cleanup, not visible at the user level but important for
+ maintenance. (E.g. converting the PCL code to use LOOP instead
+ of the old weird pre-ANSI ITERATE macro so that the code can be
+ read without being an expert in ancient languages and so that
+ can delete a thousand lines of implement-ITERATE macrology.)
+
+Matthias Hoelzl:
+ He reported and fixed COMPILE's misbehavior on macros.
+
+Espen S Johnsen:
+ He provided an ANSI-compliant version of CHANGE-CLASS for PCL.
+
+Arthur Lemmens:
+ He found and fixed a number of SBCL bugs while partially porting
+ SBCL to bootstrap under <some other Common Lisp system -- LispWorks
+ for Windows? -- which could probably be found in the sbcl-devel
+ archives>.