Add (guix build gnu-bootstrap).

* guix/build/gnu-bootstrap.scm: New file.
* Makefile.am (MODULES): Add it.

Makefile.am

@@ -172,6 +172,7 @@ MODULES =					\
   guix/build/git.scm				\
   guix/build/hg.scm				\
   guix/build/glib-or-gtk-build-system.scm	\
+  guix/build/gnu-bootstrap.scm			\
   guix/build/gnu-build-system.scm		\
   guix/build/gnu-dist.scm			\
   guix/build/guile-build-system.scm		\

guix/build/gnu-bootstrap.scm

@@ -0,0 +1,114 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2020 Timothy Sample <samplet@ngyro.com>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+;; Commentary:
+;;
+;; These procedures can be used to adapt the GNU Build System to build
+;; pure Scheme packages targeting the bootstrap Guile.
+;;
+;; Code:
+
+(define-module (guix build gnu-bootstrap)
+  #:use-module (guix build utils)
+  #:use-module (system base compile)
+  #:export (bootstrap-configure
+            bootstrap-build
+            bootstrap-install))
+
+(define (bootstrap-configure version modules scripts)
+  "Create a procedure that configures an early bootstrap package.  The
+procedure will search the MODULES directory and configure all of the
+'.in' files with VERSION.  It will then search the SCRIPTS directory and
+configure all of the '.in' files with the bootstrap Guile and its module
+and object directories."
+  (lambda* (#:key inputs outputs #:allow-other-keys)
+    (let* ((out (assoc-ref outputs "out"))
+           (guile-dir (assoc-ref inputs "guile"))
+           (guile (string-append guile-dir "/bin/guile"))
+           (moddir (string-append out "/share/guile/site/"
+                                  (effective-version)))
+           (godir (string-append out "/lib/guile/"
+                                 (effective-version)
+                                 "/site-ccache")))
+      (for-each (lambda (template)
+                  (format #t "Configuring ~a~%" template)
+                  (let ((target (string-drop-right template 3)))
+                    (copy-file template target)
+                    (substitute* target
+                      (("@VERSION@") version))))
+                (find-files modules
+                            (lambda (fn st)
+                              (string-suffix? ".in" fn))))
+      (for-each (lambda (template)
+                  (format #t "Configuring ~a~%" template)
+                  (let ((target (string-drop-right template 3)))
+                    (copy-file template target)
+                    (substitute* target
+                      (("@GUILE@") guile)
+                      (("@MODDIR@") moddir)
+                      (("@GODIR@") godir))
+                    (chmod target #o755)))
+                (find-files scripts
+                            (lambda (fn st)
+                              (string-suffix? ".in" fn))))
+      #t)))
+
+(define (bootstrap-build modules)
+  "Create a procedure that builds an early bootstrap package.  The
+procedure will search the MODULES directory and compile all of the
+'.scm' files."
+  (lambda _
+    (add-to-load-path (getcwd))
+    (for-each (lambda (scm)
+                (let* ((base (string-drop-right scm 4))
+                       (go (string-append base ".go"))
+                       (dir (dirname scm)))
+                  (format #t "Compiling ~a~%" scm)
+                  (compile-file scm #:output-file go)))
+              (find-files modules "\\.scm$"))
+    #t))
+
+(define (bootstrap-install modules scripts)
+  "Create a procedure that installs an early bootstrap package.  The
+procedure will install all of the '.scm' and '.go' files in the MODULES
+directory, and all the executable files in the SCRIPTS directory."
+  (lambda* (#:key inputs outputs #:allow-other-keys)
+    (let* ((out (assoc-ref outputs "out"))
+           (guile-dir (assoc-ref inputs "guile"))
+           (guile (string-append guile-dir "/bin/guile"))
+           (moddir (string-append out "/share/guile/site/"
+                                  (effective-version)))
+           (godir (string-append out "/lib/guile/"
+                                 (effective-version)
+                                 "/site-ccache")))
+      (for-each (lambda (scm)
+                  (let* ((base (string-drop-right scm 4))
+                         (go (string-append base ".go"))
+                         (dir (dirname scm)))
+                    (format #t "Installing ~a~%" scm)
+                    (install-file scm (string-append moddir "/" dir))
+                    (format #t "Installing ~a~%" go)
+                    (install-file go (string-append godir "/" dir))))
+                (find-files modules "\\.scm$"))
+      (for-each (lambda (script)
+                  (format #t "Installing ~a~%" script)
+                  (install-file script (string-append out "/bin")))
+                (find-files scripts
+                            (lambda (fn st)
+                              (executable-file? fn))))
+      #t)))