```common lisp
(cl:in-package #:sicl-boot)

(defun fill-boot (boot)
  (fill1 boot))

(defmethod initialize-instance :after ((boot boot) &key &allow-other-keys)
  (fill-boot boot))
```

Call function for customizing compilation environment C1.
user
```common lisp
(cl:in-package #:sicl-boot)

(defun fill-boot (boot)
  (customize-c1 boot)
  (fill1 boot))

(defmethod initialize-instance :after ((boot boot) &key &allow-other-keys)
  (fill-boot boot))
```
assistant