Hello.
I use SLIME with SBCL; I have two instances of SBCL in my system (sometimes more); one is system-wide installation, second is project-local, both are of the same version, but with possibly different features. Both use SLIME (project-local version loads swank by hand). Problem is that system-wide SBCL is threaded, and project-local one is not; thus, .fasl files generated by one are unreadable to other. I don't want project-local SBCL and SLIME to mess with my system-wide settings and I'd prefer to have it leave any files outside project dir alone.
I made a small patch against current CVS to swank to make it possible to keep FASL files in source directory; now it is turned on by pushing :SWANK-FASL-IN-PLACE to *FEATURES*; I couldn't think of better way of signalling swank-loader.lisp that we want to have FASL with sources before loading it (i.e. before (DEFPACKAGE)s and (DEFVAR)s). If this way is ok, please apply this patch; I don't insist on this particular way of communicationg with loader (it seems kludgy), if there is better one, please treat this post as yet another feature request.