diff --git a/collects/meta/web/build.rkt b/collects/meta/web/build.rkt
index 716b4aaa0b..958dc4143a 100755
--- a/collects/meta/web/build.rkt
+++ b/collects/meta/web/build.rkt
@@ -13,8 +13,10 @@ exec "$exe" "$0" "$@"
          "config.rkt" "navbar.rkt")
 
 (define build-mode #f)
+(define output-dir (current-directory))
 (define distribute? #f)
 (define warn? #t)
+(define extra-file #f)
 
 (command-line
  #:once-any
@@ -31,36 +33,46 @@ exec "$exe" "$0" "$@"
   "  (defaults to the current directory)"
   (unless (directory-exists? dir)
     (printf "Creating \"~a\"\n" dir) (make-directory dir))
-  (current-directory dir)]
+  (set! output-dir dir)]
  [("-f")
   "avoid warning about directory cleanup"
   (set! warn? #f)]
  [("-d" "--dist")
   "distribute resulting content"
   "  (will only work with the right access to the servers)"
-  (set! distribute? #t)])
+  (set! distribute? #t)]
+ [("-e" "--extra") extra
+  "extra file to render more content"
+  (set! extra-file extra)])
 
 (unless build-mode (raise-user-error 'build "build mode not specified"))
 
 (define-runtime-path here ".")
-(let ([build (file-or-directory-identity (current-directory))])
+(let ([build (file-or-directory-identity output-dir)])
   (let loop ([dir here])
     (if (equal? build (file-or-directory-identity dir))
       (raise-user-error 'build "might clobber sources, refusing to build")
       (let-values ([(base name dir?) (split-path dir)])
         (when base (loop base))))))
 
-(let ([paths (sort (map path->string (directory-list)) string<?)])
-  (when (pair? paths)
-    (if (or (not warn?)
-            (begin (printf "Directory not empty, these will be deleted: ~a.\n"
-                           (string-join paths ", "))
-                   (printf "Continue? ") (flush-output)
-                   (regexp-match? #rx" *[yY]" (read-line))))
-      (for-each delete-directory/files paths)
-      (raise-user-error 'build "Aborting."))))
+(parameterize ([current-directory output-dir])
+  (let ([paths (sort (map path->string (directory-list)) string<?)])
+    (when (pair? paths)
+      (if (or (not warn?)
+              (begin (printf "Directory not empty, these will be deleted: ~a.\n"
+                             (string-join paths ", "))
+                     (printf "Continue? ") (flush-output)
+                     (regexp-match? #rx" *[yY]" (read-line))))
+        (for-each delete-directory/files paths)
+        (raise-user-error 'build "Aborting.")))))
 
 (printf "Building ~a content...\n" build-mode)
-(parameterize ([url-roots (and (eq? 'web build-mode) sites)]) (render-all))
-(when distribute? (printf "Distributing...\n") (distribute distributions))
+(parameterize ([url-roots (and (eq? 'web build-mode) sites)])
+  (when (and extra-file (file-exists? extra-file))
+    (dynamic-require extra-file #f))
+  (parameterize ([current-directory output-dir])
+    (render-all)
+    (when distribute?
+      (printf "Distributing...\n")
+      (distribute distributions))))
 (printf "Done.\n")