eXtensible Component Verifier and Builder for Common-Lisp.
XCVB is a Common Lisp build system.
XCVB hasn't seen much development since 2012. It works, but it has not reached its full potential.
I don't intend to maintain XCVB anymore unless there is funding for it. Considering the extremely conservative nature of the Common Lisp community, an incremental evolution to do things with an ASDF 4 would be more likely to succeed, too. See the ASDF TODO file for that.
XCVB was originally written with ASDF 1, and it was meant to eventually replace ASDF. Due to various circumstances, my efforts have shifted towards developing ASDF itself, which has much evolved since those times.
That said, if you're going to write a next generation build system in and/or for Common Lisp, there is probably plenty of ideas and maybe even code to salvage from XCVB and its own TODO.
You may also consider my blog post on build systems.