Add GNU Guix development environment helper.

* package.scm: New file.
* README.md: Document it.

README.md

@@ -50,16 +50,23 @@ Requirements
 
 GNU Guile >= 2.0.9
 
-Building
+Building from Git
---------
+-----------------
 
 Haunt uses the familiar GNU build system.  GNU automake, autoconf, and
-make are required to build from source.
+make are required to build from a git checkout.
 
 ```
 ./bootstrap && ./configure && make
 ```
 
+GNU Guix users can create a build environment with all necessary
+dependencies using the handy `guix environment` tool:
+
+```
+guix environment -l package.scm
+```
+
 License
 -------
 

package.scm

@@ -0,0 +1,47 @@
+;;; Haunt --- Static site generator for GNU Guile
+;;; Copyright © 2015 David Thompson <davet@gnu.org>
+;;;
+;;; This file is part of Haunt.
+;;;
+;;; Haunt 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.
+;;;
+;;; Haunt 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 Haunt.  If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+;;
+;; Development environment for GNU Guix.
+;;
+;;; Code:
+
+(use-modules (guix packages)
+             (guix licenses)
+             (guix build-system gnu)
+             (gnu packages)
+             (gnu packages autotools)
+             (gnu packages guile))
+
+(package
+  (name "haunt")
+  (version "0.0")
+  (source #f)
+  (build-system gnu-build-system)
+  (native-inputs
+   `(("autoconf" ,autoconf)
+     ("automake" ,automake)))
+  (inputs
+   `(("guile" ,guile-2.0)))
+  (synopsis "Functional, composable static site generator")
+  (description "Haunt is a static site generator written in Guile
+Scheme.  Haunt features a functional build system and an extensible
+interface for reading site content in any format.")
+  (home-page "https://git.dthompson.us/haunt.git")
+  (license gpl3+))