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diff --git a/apps/i18n.scm b/apps/i18n.scm
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+;;; Harmonic Flow web site
+
+(define-module (apps i18n)
+  #:use-module (haunt asset)
+  #:use-module (haunt artifact)
+  #:use-module (haunt utils)
+  #:use-module ((guix i18n) #:select (%package-text-domain))
+  #:use-module (ice-9 match)
+  #:use-module (sexp-xgettext)
+  #:use-module (srfi srfi-1)
+  #:export (G_
+            N_
+            C_
+            NC_
+            %current-ietf-tag
+            %current-lang
+            %current-lingua
+            builder->localized-builder
+            builders->localized-builders
+            ietf-tags-file-contents
+            localized-root-path))
+
+(define %gettext-domain
+  "guix-website")
+
+(bindtextdomain %gettext-domain (getcwd))
+(bind-textdomain-codeset %gettext-domain "UTF-8")
+(textdomain %gettext-domain)
+(bindtextdomain %package-text-domain (getcwd))
+(bind-textdomain-codeset %package-text-domain "UTF-8")
+
+;; NOTE: The sgettext macros have no hygiene because they use
+;; datum->syntax and do not preserve the semantics of anything looking
+;; like an sgettext macro.  This is an exceptional use case; do not
+;; try this at home.
+
+(define-syntax G_
+  sgettext)
+
+(set-simple-keywords! '(G_))
+
+(define-syntax N_ ;like ngettext
+  sngettext)
+
+(define-syntax C_ ;like pgettext
+  spgettext)
+
+(define-syntax NC_ ;like npgettext
+  snpgettext)
+
+(set-complex-keywords! '(N_ C_ NC_))
+
+(define %current-lingua
+  ;; strip the character encoding:
+  (car (string-split (setlocale LC_ALL) #\.)))
+
+(define-syntax ietf-tags-file-contents
+  (identifier-syntax
+   (force (delay (call-with-input-file
+                     "po/ietf-tags.scm"
+                   (lambda (port) (read port)))))))
+
+
+(define %current-ietf-tag
+  (or (assoc-ref ietf-tags-file-contents %current-lingua)
+      "en"))
+
+(define %current-lang
+  (car (string-split %current-ietf-tag #\-)))
+
+(define* (localized-root-path url #:key (lingua %current-ietf-tag))
+  "Given a URL as used in a href attribute, return the URL prefix
+'builder->localized-builder' would use for the URL when called with
+LINGUA."
+  (if (or (string-suffix? ".html" url)
+          (string-suffix? "/" url))
+      (string-append lingua "/")
+      ""))
+
+(define (first-value arg)
+  "For some reason the builder returned by static-directory returns
+multiple values.  This procedure is used to retain only the first
+return value.  TODO: This should not be necessary."
+  arg)
+
+(define (builder->localized-builder builder)
+  "Return a Haunt builder procedure generated from an existing BUILDER
+with translations for the current system locale coming from
+sexp-xgettext."
+  (compose
+   (lambda (pages-and-assets)
+     (map (match-lambda
+            ((? artifact? artifact)               ;Haunt >= 0.2.5
+             (let ((new-name (string-append
+                              (localized-root-path (artifact-file-name artifact))
+                              (artifact-file-name artifact))))
+               (make-artifact new-name
+                              (artifact-writer artifact)))))
+      pages-and-assets))
+   (lambda (site posts)
+     (first-value (builder site posts)))))
+
+(define (builders->localized-builders builders)
+  "Return a list of new Haunt builder procedures generated from
+BUILDERS and localized via sexp-xgettext for the current system
+locale."
+  (flatten
+   (map-in-order
+    builder->localized-builder
+    builders)))