--- a
+++ b/contrib/sb-executable/sb-executable.lisp
@@ -0,0 +1,50 @@
+(cl:defpackage :sb-executable
+  (:use :cl :sb-ext :sb-alien)
+  (:export :make-executable :copy-stream)
+  ;; (what else should we be exporting?)
+  )
+
+(cl:in-package :sb-executable)
+
+(defvar *stream-buffer-size* 8192)
+(defun copy-stream (from to)
+  "Copy into TO from FROM until end of the input stream, in blocks of
+*stream-buffer-size*.  The streams should have the same element type."
+  (unless (subtypep (stream-element-type to) (stream-element-type from))
+    (error "Incompatible streams ~A and ~A." from to))
+  (let ((buf (make-array *stream-buffer-size*
+			 :element-type (stream-element-type from))))
+    (loop
+     (let ((pos (read-sequence buf from)))
+       (when (zerop pos) (return))
+       (write-sequence buf to :end pos)))))
+
+(defvar *exec-header*
+  "#!/bin/sh --
+exec sbcl --noinform ~{~A ~}--eval \"(with-open-file (i \\\"$0\\\" :element-type '(unsigned-byte 8)) (read-line i) (read-line i) (load i) (quit))\" --end-toplevel-options ${1+\"$@\"}
+")
+
+(defun make-executable (output-file fasls
+			&key (runtime-flags '("--disable-debugger"
+					      "--userinit /dev/null"
+					      "--sysinit /dev/null")))
+  "Write an executable called OUTPUT-FILE which can be run from the shell, by 'linking' together code from FASLS.  Actually works by concatenating them and prepending a #! header"
+  (with-open-file (out output-file :direction :output
+		       :element-type '(unsigned-byte 8))
+    (write-sequence (map 'vector #'char-code
+			 (format nil *exec-header* runtime-flags)) out)
+    (dolist (input-file (if (listp fasls) fasls (list fasls)))
+      (with-open-file (in (merge-pathnames input-file
+					   (make-pathname :type "fasl"))
+			  :element-type '(unsigned-byte 8))
+	(copy-stream in out))))
+  (let* ((out-name (namestring output-file))
+	 (prot (elt (multiple-value-list (sb-unix:unix-stat out-name)) 3)))
+    (sb-unix::void-syscall ("chmod" c-string int)
+			   out-name
+			   (logior prot
+				   (if (logand prot #o400) #o100)
+				   (if (logand prot  #o40)  #o10)
+				   (if (logand prot   #o4)   #o1)))))
+			 
+