diff --git a/src/computersandblues/lodestone/app.cljs b/src/computersandblues/lodestone/app.cljs
index 3cc4915..8234e39 100644
--- a/src/computersandblues/lodestone/app.cljs
+++ b/src/computersandblues/lodestone/app.cljs
@@ -349,7 +349,7 @@
         refresh-id (js/Date.now)]
     (swap! state update-in [:section/posts :loading] conj refresh-id)
     (-> (js/Promise.all #js [(db/count! ::db/posts)
-                             (-> (db/open-cursor! ::db/posts db/all "prev")
+                             (-> (db/open-cursor! ::db/posts "created_at" db/all "prev")
                                  (db/transduce-cursor xform))])
         (.then (fn [[total displayed-posts]]
                  (swap! state update :section/posts #(-> (assoc % :total total)
@@ -407,12 +407,15 @@
 
 ;; database
 
-(def db-version 1)
+(def db-version 2)
 
 (def migrations
-  {1 (fn migration-0001 [db]
+  {1 (fn migration-0001 [db _]
        (db/create-object-store! db ::db/application {:keyPath "id"})
-       (db/create-object-store! db ::db/posts {:keyPath "id"}))})
+       (db/create-object-store! db ::db/posts {:keyPath "id"}))
+   2 (fn migration-0002 [_ txn]
+       (-> (db/open-store txn ::db/posts "readwrite")
+           (db/create-index! "created_at" "created_at" {:unique false})))})
 
 ;; go go go
 
diff --git a/src/computersandblues/lodestone/database.cljs b/src/computersandblues/lodestone/database.cljs
index 74eb843..89faecc 100644
--- a/src/computersandblues/lodestone/database.cljs
+++ b/src/computersandblues/lodestone/database.cljs
@@ -21,25 +21,34 @@
          (.addEventListener "upgradeneeded"
                             (fn [ev]
                               (let [db (.-result request)
-                                    old-version (.-oldVersion ev)]
+                                    old-version (.-oldVersion ev)
+                                    txn (-> ev .-target .-transaction)]
                                 (js/console.log ::upgradeneeded ev db)
                                 (doseq [version (range (inc old-version) (inc db-version))
                                         :let [migration (migrations version)]]
-                                  (migration db)))))
+                                  (migration db txn)))))
                                         ; we don't add a listener for "blocked" events because we handle "versionchange" above
          (.addEventListener "error" (fn [ev] (reject (.-result request) ev))))))))
 
 (defn open-store
-  ([db store-id]
-   (open-store db store-id "readonly"))
-  ([db store-id permissions]
+  ([db-or-txn store-id]
+   (open-store db-or-txn store-id "readonly"))
+  ([db-or-txn store-id permissions]
    (let [store-id (str store-id) ; simplifies using keywords as store identifiers
-         txn (.transaction db store-id permissions)]
+         txn (if (instance? js/IDBTransaction db-or-txn)
+               db-or-txn
+               (.transaction db-or-txn store-id permissions))]
      (.objectStore txn store-id))))
 
 (defn create-object-store! [db store-id key-opts]
   (.createObjectStore db (str store-id) (clj->js key-opts)))
 
+(defn create-index!
+  ([store idx-name fields]
+   (create-index! store idx-name fields {}))
+  ([store idx-name fields opts]
+   (.createIndex store (str idx-name) (clj->js fields) (clj->js opts))))
+
 (defn- promisify [request]
   (js/Promise. (fn [resolve reject]
                  (doto request
@@ -70,7 +79,10 @@
   ([store-id key-range] (open-cursor! store-id key-range "next"))
   ([store-id key-range direction]
    (let [store (open-store @+db+ store-id)]
-     (.openCursor store key-range direction))))
+     (.openCursor store key-range direction)))
+  ([store-id idx-name key-range direction]
+   (let [store (open-store @+db+ store-id)]
+     (.openCursor (.index store (str idx-name)) key-range direction))))
 
 #_(defn logging [f]
   (let [n (volatile! 0)]