All you need is asdf 3.1.2 or later and Clamp has to be somewhere in your ~/common-lisp/ directory. Once you do that, just use (require :asdf) and (require :clamp).
I'll just include a reference to this[0] in the readme.
I get this error when running from the Clamp directory:
$ sbcl
* (require :asdf)
NIL
* (require :clamp)
ASDF could not load clamp because
Error while trying to load definition for system clamp from pathname
~/Clamp/clamp.asd:
The name "ASDF-USER" does not designate any package..
debugger invoked on a LOAD-SYSTEM-DEFINITION-ERROR in thread
#<THREAD "initial thread" RUNNING {1002998F33}>:
Error while trying to load definition for system clamp from pathname
~/Clamp/clamp.asd:
The name "ASDF-USER" does not designate any package.
Type HELP for debugger help, or (SB-EXT:QUIT) to exit from SBCL.
restarts (invokable by number or by possibly-abbreviated name):
0: [RETRY ] Retry EVAL of current toplevel form.
1: [CONTINUE ] Ignore error and continue loading file "~/Clamp/clamp.asd".
2: [ABORT ] Abort loading file "~/Clamp/clamp.asd".
3: [REINITIALIZE-SOURCE-REGISTRY-AND-RETRY] Retry finding system clamp after
reinitializing the
source-registry.
4: Exit debugger, returning to top
level.
((FLET #:LAMBDA2286 :IN ASDF::LOAD-SYSDEF)
#<SB-KERNEL:SIMPLE-PACKAGE-ERROR "The name ~S does not designate any package."
{10049EB763}>)
0]
