```common lisp
(cl:in-package #:common-lisp-user)

(asdf:defsystem :clobber
  :components
  ((:file "packages")
   (:file "clobber" :depends-on ("packages"))
   (:file "demo" :depends-on ("clobber"))
   (:file "demo2" :depends-on ("clobber"))))
```

Define system in package ASDF-USER.
user
```common lisp
(cl:in-package #:asdf-user)

(defsystem :clobber
  :components
  ((:file "packages")
   (:file "clobber" :depends-on ("packages"))
   (:file "demo" :depends-on ("clobber"))
   (:file "demo2" :depends-on ("clobber"))))
```
assistant