website: Update manifest.

* website/guix.packages: Rename to...
* website/manifest.scm: ...this.
* website/README: Update.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

website/README

@@ -14,21 +14,38 @@ following command to install all the software needed to build the
 website:
 
 #+BEGIN_EXAMPLE
-$ guix package -i git glibc-locales gnutls guile guile-json guile-syntax-highlight guix haunt
+  guix package -m manifest.scm
 #+END_EXAMPLE
 
+*Note*: the packages =guix= and =haunt= should have the same version of Guile,
+otherwise building the website is slow and raises bunch of warnings.  The
+manifest file takes care.
+
 * Running the website
 
 To try out the website locally while you work on it, run the following
 commands:
 
 #+BEGIN_EXAMPLE
-$ cd path/to/guix-artwork/website
-$ export GUILE_LOAD_PATH=$(guix build guile-syntax-highlight)/share/guile/site/3.0:$GUILE_LOAD_PATH
-$ LC_ALL=en_US.utf8 GUIX_WEB_SITE_LOCAL=yes haunt build
-$ haunt serve
+  cd path/to/guix-artwork/website
 #+END_EXAMPLE
 
+** Build locally
+#+begin_example
+  GUIX_WEB_SITE_LOCAL=yes guix environment -C -m manifest.scm                            \
+                          -E GUIX_LOCPATH -E LANG --share=$HOME/.guix-profile/lib/locale \
+                          -E GUIX_WEB_SITE_LOCAL  --share=/tmp                           \
+                          -- haunt build
+#+end_example
+
+** Serve locally
+#+begin_example
+  guix environment -CN -m manifest.scm                                \
+       -E GUIX_LOCPATH -E LANG --share=$HOME/.guix-profile/lib/locale \
+       --share=/tmp                                                   \
+       -- haunt serve -w
+#+end_example
+
 Then, visit http://localhost:8080/en/guix.html in a web browser.
 
 You can stop the server pressing ~Ctrl + C~ twice.

website/guix.packages

@@ -1,16 +0,0 @@
-;;; Packages required to develop the website.
-;;; (See guix package --manifest option for more details on this file).
-
-(use-modules (guix profiles)
-	     (gnu packages))
-
-
-(define dev-packages
-  (list "glibc-locales"
-	"guile@2.2"
-	"guile-syntax-highlight"
-	"guix"
-	"haunt"))
-
-
-(map specification->package dev-packages)

website/manifest.scm

@@ -0,0 +1,30 @@
+(use-modules (guix packages)
+             ((gnu packages package-management) #:select (guix))
+             ((gnu packages guile-xyz)          #:select (haunt))
+             (srfi srfi-1))
+
+(define the-good-guile
+  (car (assoc-ref (package-native-inputs guix) "guile")))
+
+(define haunt-the-ghost
+  (package
+    (inherit haunt)
+    (name "haunt-for-guix-website")
+    (inputs
+     `(("guile" ,the-good-guile)
+       ,@(alist-delete "guile" (package-inputs haunt))))))
+
+(packages->manifest
+ (append
+  ;; Guile needs to be compatible
+  (list
+   guix
+   the-good-guile
+   haunt-the-ghost)
+
+  ;; Other packages
+  (map specification->package
+       (list
+        "glibc-locales"
+        "git"
+        "guile-syntax-highlight"))))