diff --git a/src/dispatcher-tree.rkt b/src/dispatcher-tree.rkt
index 93532ef..1a43458 100644
--- a/src/dispatcher-tree.rkt
+++ b/src/dispatcher-tree.rkt
@@ -8,7 +8,8 @@
          (prefix-in sequencer: web-server/dispatchers/dispatch-sequencer)
          (prefix-in lift: web-server/dispatchers/dispatch-lift)
          (prefix-in filter: web-server/dispatchers/dispatch-filter)
-         "config.rkt")
+         "config.rkt"
+         "url-utils.rkt")
 
 (provide
  ; syntax to make the hashmap from names
@@ -43,9 +44,9 @@
               (pathprocedure:make "/" (hash-ref ds 'page-home))
               (pathprocedure:make "/proxy" (hash-ref ds 'page-proxy))
               (pathprocedure:make "/search" (hash-ref ds 'page-global-search))
-              (filter:make #px"^/[a-zA-Z0-9-]{3,50}/wiki/Category:.+$" (lift:make (hash-ref ds 'page-category)))
-              (filter:make #px"^/[a-zA-Z0-9-]{3,50}/wiki/.+$" (lift:make (hash-ref ds 'page-wiki)))
-              (filter:make #px"^/[a-zA-Z0-9-]{3,50}/search$" (lift:make (hash-ref ds 'page-search)))
-              (filter:make #px"^/[a-zA-Z0-9-]{3,50}(/(wiki(/)?)?)?$" (lift:make (hash-ref ds 'redirect-wiki-home)))
+              (filter:make (pregexp (format "^/~a/wiki/Category:.+$" wikiname-regex)) (lift:make (hash-ref ds 'page-category)))
+              (filter:make (pregexp (format "^/~a/wiki/.+$" wikiname-regex)) (lift:make (hash-ref ds 'page-wiki)))
+              (filter:make (pregexp (format "^/~a/search$" wikiname-regex)) (lift:make (hash-ref ds 'page-search)))
+              (filter:make (pregexp (format "^/~a(/(wiki(/)?)?)?$" wikiname-regex)) (lift:make (hash-ref ds 'redirect-wiki-home)))
               (hash-ref ds 'static-dispatcher)
               (lift:make (hash-ref ds 'page-not-found)))))))
diff --git a/src/page-wiki.rkt b/src/page-wiki.rkt
index 96410d0..795f34c 100644
--- a/src/page-wiki.rkt
+++ b/src/page-wiki.rkt
@@ -143,7 +143,7 @@
                        (λ (href)
                          ((compose1
                            (λ (href) (regexp-replace #rx"^(/wiki/.*)" href (format "/~a\\1" wikiname)))
-                           (λ (href) (regexp-replace #px"^https://([a-zA-Z0-9-]{3,50}).fandom.com(/wiki/.*)" href "/\\1\\2")))
+                           (λ (href) (regexp-replace (pregexp (format "^https://(~a)\\.fandom\\.com(/wiki/.*)" wikiname-regex)) href "/\\1\\2")))
                           href)))
                 ; add noreferrer to a.image
                 (curry u
diff --git a/src/url-utils.rkt b/src/url-utils.rkt
index 934a228..cefee19 100644
--- a/src/url-utils.rkt
+++ b/src/url-utils.rkt
@@ -3,6 +3,8 @@
          "pure-utils.rkt")
 
 (provide
+ ; regex to match wiki names
+ wikiname-regex
  ; make a query string from an association list of strings
  params->query
  ; make a proxied version of a fandom url
@@ -13,6 +15,8 @@
 (module+ test
   (require "typed-rackunit.rkt"))
 
+(define wikiname-regex "[a-zA-Z0-9-]{3,50}")
+
 ;; https://url.spec.whatwg.org/#urlencoded-serializing
 
 (define urlencoded-set '(#\! #\' #\( #\) #\~ ; urlencoded set
@@ -57,7 +61,7 @@
 
 (: is-fandom-url? (String -> Boolean))
 (define (is-fandom-url? url)
-  (regexp-match? #px"^https://static.wikia.nocookie.net/|^https://[a-zA-Z0-9-]{3,50}.fandom.com/" url))
+  (regexp-match? (pregexp (format "^https://static\\.wikia\\.nocookie\\.net/|^https://~a\\.fandom\\.com/" wikiname-regex)) url))
 (module+ test
   (check-true (is-fandom-url? "https://static.wikia.nocookie.net/wikiname/images/2/2f/SomeImage.jpg/revision/latest?cb=20110210094136"))
   (check-true (is-fandom-url? "https://test.fandom.com/wiki/Some_Page"))