I have real trouble deciphering the new make-build code but I have come to the conclusion that the :DLL target has been eliminated. The current :DLL target claims to "Link together all the dynamic library used by this system into a single one." which is not what ECL's :DLL target was doing. ECL's :DLL/:SHARED-LIBRARY target did the same as :STATIC-LIBRARY, which is to link all FASL files into a single, linkable file, but in the shared library form. The elimination of this feature and the replacement with a possibly empty behavior (I see no opeartion associated to DLL at all), breaks ECL's users code and expectations, having had already some bug reports for that. The worse thing is that I no longer seem to understand ASDF's internal's logic well enough to provide any reliable kind of fix, but what I attached seems to do the job just as well. In this patch, since the DLL operation does nothing on any other platform, I took the liberty to condition it on ECL/MKCL Juanjo -- Instituto de Física Fundamental, CSIC c/ Serrano, 113b, Madrid 28006 (Spain) http://quinfog.iff.csic.es