Paul Dietz has added some features to rt for his GCL ANSI Test Suite. These extensions have been incorporated into sbcl's sb-rt package and Kevin Rosenberg's cl-rt Debian package.
Kevin Rosenberg's git repository: http://git.kpe.io/?p=rt.git;a=summary
Old version from the CMU AI Repository: http://www.cs.cmu.edu/afs/cs/project/ai-repository/ai/lang/lisp/code/testing/rt/0.html
obsolete