diff --git a/build-example-site.sh b/build-example-site.sh
index 1bfc3b3..50735d9 100755
--- a/build-example-site.sh
+++ b/build-example-site.sh
@@ -6,7 +6,7 @@ SHA=$(git rev-parse HEAD)
 
 lein 'do' clean, cljsbuild once prod-npm, cljsbuild once prerender
 
-node target/cljsbuild/prerender/main.js
+node target/cljsbuild/prerender/main.js target/prod-npm/public/
 
 lein codox
 
diff --git a/demo/sitetools/prerender.cljs b/demo/sitetools/prerender.cljs
index 20cdc32..f3508a4 100644
--- a/demo/sitetools/prerender.cljs
+++ b/demo/sitetools/prerender.cljs
@@ -2,18 +2,18 @@
   (:require [reagent.debug :refer-macros [log]]
             [sitetools.core :as tools]
             [sitetools.server :as server]
-            [reagentdemo.core :as demo]))
+            [reagentdemo.core :as demo]
+            [path :as path]))
 
 (defn -main [& args]
   (log "Generating site")
   (demo/init!)
-  (let [conf @tools/config
-        conf (assoc conf :timestamp (str "?" (js/Date.now)))
-        {:keys [site-dir pages]} conf]
+  (let [[js-resource-path] args
+        {:keys [site-dir pages] :as conf} (assoc @tools/config :js-resource-path js-resource-path)]
+    (server/write-resources site-dir conf)
     (doseq [f (keys pages)]
-      (server/write-file (->> f tools/to-relative (server/path-join site-dir))
-                         (server/gen-page f conf)))
-    (server/write-resources site-dir conf))
+      (server/write-file (->> f tools/to-relative (path/join site-dir))
+                         (server/gen-page f conf))))
   (log "Wrote site")
   (js/process.exit 0))
 
diff --git a/demo/sitetools/server.cljs b/demo/sitetools/server.cljs
index 221ff86..9943ea1 100644
--- a/demo/sitetools/server.cljs
+++ b/demo/sitetools/server.cljs
@@ -6,7 +6,11 @@
             [reagent.dom.server :as server]
             [reagent.debug :refer-macros [dbg log dev?]]
             [reagent.interop :as i :refer-macros [$ $!]]
-            [sitetools.core :as tools]))
+            [sitetools.core :as tools]
+            [md5-file :as md5-file]
+            [path :as path]
+            [fs :as fs]
+            [path :as path]))
 
 
 ;;; Static site generation
@@ -18,23 +22,31 @@
 (defn danger [t s]
   [t {:dangerouslySetInnerHTML {:__html s}}])
 
-(defn html-template [{:keys [title body-html timestamp page-conf
-                             js-file css-file main-div]}]
-  (let [main (str js-file timestamp)]
-    (server/render-to-static-markup
-     [:html
-      [:head
-       [:meta {:charset 'utf-8}]
-       [:meta {:name 'viewport
-               :content "width=device-width, initial-scale=1.0"}]
-       [:base {:href (-> page-conf :page-path base)}]
-       [:link {:href (str css-file timestamp) :rel 'stylesheet}]
-       [:title title]]
-      [:body
-       [:div {:id main-div} (danger :div body-html)]
-       (danger :script (str "var pageConfig = "
-                            (-> page-conf clj->js js/JSON.stringify)))
-       [:script {:src main :type "text/javascript"}]]])))
+(defn add-cache-buster [resource-path path]
+  (let [h (md5-file/sync (path/join resource-path path))]
+    (str path "?" (subs h 0 6))))
+
+(defn html-template [{:keys [title body-html page-conf
+                             js-file css-file main-div
+                             js-resource-path site-dir]}]
+  (server/render-to-static-markup
+    [:html
+     [:head
+      [:meta {:charset 'utf-8}]
+      [:meta {:name 'viewport
+              :content "width=device-width, initial-scale=1.0"}]
+      [:base {:href (-> page-conf :page-path base)}]
+      [:link {:href (add-cache-buster site-dir css-file)
+              :rel "stylesheet"}]
+      [:title title]]
+     [:body
+      [:div
+       {:id main-div}
+       (danger :div body-html)]
+      (danger :script (str "var pageConfig = "
+                           (-> page-conf clj->js js/JSON.stringify)))
+      [:script {:src (add-cache-buster js-resource-path js-file)
+                :type "text/javascript"}]]]))
 
 (defn gen-page [page-path conf]
   (tools/emit [:set-page page-path])
@@ -46,26 +58,20 @@
                                :page-conf {:page-path page-path}
                                :body-html bhtml)))))
 
-(defn fs [] (js/require "fs"))
-(defn path [] (js/require "path"))
-
 (defn mkdirs [f]
   (doseq [d (reductions #(str %1 "/" %2)
-                        (-> ($ (path) normalize f)
+                        (-> (path/normalize f)
                             (string/split #"/")))]
-    (when-not ($ (fs) existsSync d)
-      ($ (fs) mkdirSync d))))
+    (when-not (fs/existsSync d)
+      (fs/mkdirSync d))))
 
 (defn write-file [f content]
   (log "Write" f)
-  (mkdirs ($ (path) dirname f))
-  ($ (fs) writeFileSync f content))
-
-(defn path-join [& paths]
-  (apply ($ (path) :join) paths))
+  (mkdirs (path/dirname f))
+  (fs/writeFileSync f content))
 
 (defn write-resources [dir {:keys [css-file css-infiles]}]
-  (write-file (path-join dir css-file)
+  (write-file (path/join dir css-file)
               (->> css-infiles
-                   (map #($ (fs) readFileSync %))
+                   (map #(fs/readFileSync %))
                    (string/join "\n"))))
diff --git a/package-lock.json b/package-lock.json
index 0c3141b..a697e01 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -3922,6 +3922,12 @@
             "integrity": "sha1-2TPOuSBdgr3PSIb2dCvcK03qFG0=",
             "dev": true
         },
+        "md5-file": {
+            "version": "4.0.0",
+            "resolved": "https://registry.npmjs.org/md5-file/-/md5-file-4.0.0.tgz",
+            "integrity": "sha512-UC0qFwyAjn4YdPpKaDNw6gNxRf7Mcx7jC1UGCY4boCzgvU2Aoc1mOGzTtrjjLKhM5ivsnhoKpQVxKPp+1j1qwg==",
+            "dev": true
+        },
         "md5.js": {
             "version": "1.3.4",
             "resolved": "https://registry.npmjs.org/md5.js/-/md5.js-1.3.4.tgz",
diff --git a/package.json b/package.json
index ab193d0..92669f7 100644
--- a/package.json
+++ b/package.json
@@ -12,6 +12,7 @@
     "karma": "2.0.0",
     "karma-chrome-launcher": "2.2.0",
     "karma-cljs-test": "0.1.0",
-    "karma-junit-reporter": "1.2.0"
+    "karma-junit-reporter": "1.2.0",
+    "md5-file": "^4.0.0"
   }
 }