diff --git a/lib/archive-file-mappings.rkt b/lib/archive-file-mappings.rkt
index 4aa8a69..ba013ab 100644
--- a/lib/archive-file-mappings.rkt
+++ b/lib/archive-file-mappings.rkt
@@ -11,7 +11,7 @@
  url-segments->guess-title)
 
 (define (local-encoded-url->segments str) ; '("wiki" "Page_title")
-  (map path/param-path (url-path (string->url str))))
+  (map path/param-path (fix-semicolons-url-path (url-path (string->url str)))))
 
 (define (url-segments->basename segments) ; "Page_title" filename encoded, no extension or dir prefix
   (define extra-encoded (map (λ (s) (bytes->string/latin-1 (percent-encode s filename-set #f))) (cdr segments)))
diff --git a/lib/url-utils.rkt b/lib/url-utils.rkt
index 4722d49..3fb4310 100644
--- a/lib/url-utils.rkt
+++ b/lib/url-utils.rkt
@@ -1,5 +1,6 @@
 #lang typed/racket/base
 (require racket/string
+         typed/net/url-structs
          "pure-utils.rkt")
 (require/typed web-server/http/request-structs
                [#:opaque Header header?])
@@ -20,7 +21,10 @@
  ; pass in a header, headers, or something useless. they'll all combine into a list
  build-headers
  ; try to follow wikimedia's format for which characters should be encoded/replaced in page titles for the url
- page-title->path)
+ page-title->path
+ ; path/param eats semicolons into params, which need to be fixed back into semicolons
+ fix-semicolons-url-path
+ fix-semicolons-url)
 
 (module+ test
   (require "typed-rackunit.rkt"))
@@ -106,3 +110,20 @@
 (: page-title->path (String -> Bytes))
 (define (page-title->path title)
   (percent-encode (regexp-replace* " " title "_") path-set #f))
+
+(: fix-semicolons-url-path ((Listof Path/Param) -> (Listof Path/Param)))
+(define (fix-semicolons-url-path pps)
+  (for/list ([pp pps])
+    (define path (path/param-path pp))
+    (if (or (null? (path/param-param pp))
+            (symbol? path))
+        pp
+        ;; path/param does have params, which need to be fixed into a semicolon.
+        (path/param
+         (string-append path ";" (string-join (path/param-param pp) ";"))
+         null))))
+
+(: fix-semicolons-url (URL -> URL))
+(define (fix-semicolons-url orig-url)
+  (struct-copy url orig-url [path (fix-semicolons-url-path (url-path orig-url))]))
+
diff --git a/src/dispatcher-tree.rkt b/src/dispatcher-tree.rkt
index 315638a..48e8ebb 100644
--- a/src/dispatcher-tree.rkt
+++ b/src/dispatcher-tree.rkt
@@ -59,16 +59,5 @@
   (make-semicolon-fixer-dispatcher tree))
 
 (define ((make-semicolon-fixer-dispatcher orig-dispatcher) conn orig-req)
-  (define orig-uri (request-uri orig-req))
-  (define pps (url-path orig-uri)) ; list of path/param structs
-  (define new-path
-    (for/list ([pp pps])
-      (if (null? (path/param-param pp))
-          pp
-          ;; path/param does have params, which need to be fixed into a semicolon.
-          (path/param
-           (string-append (path/param-path pp) ";" (string-join (path/param-param pp) ";"))
-           null))))
-  (define new-uri (struct-copy url orig-uri [path new-path]))
-  (define new-req (struct-copy request orig-req [uri new-uri]))
+  (define new-req (struct-copy request orig-req [uri (fix-semicolons-url (request-uri orig-req))]))
   (orig-dispatcher conn new-req))