diff --git a/src/reagent/impl/batching.cljs b/src/reagent/impl/batching.cljs
index 31ad329..bd9fb57 100644
--- a/src/reagent/impl/batching.cljs
+++ b/src/reagent/impl/batching.cljs
@@ -27,8 +27,8 @@
           fake-raf))))
 
 (defn compare-mount-order [c1 c2]
-  (- (.' c2 :cljsMountOrder)
-     (.' c1 :cljsMountOrder)))
+  (- (.' c1 :cljsMountOrder)
+     (.' c2 :cljsMountOrder)))
 
 (defn run-queue [a]
   ;; sort components by mount order, to make sure parents
diff --git a/src/reagent/impl/component.cljs b/src/reagent/impl/component.cljs
index 483e09c..e76fbdf 100644
--- a/src/reagent/impl/component.cljs
+++ b/src/reagent/impl/component.cljs
@@ -105,7 +105,7 @@
       (this-as c
                (f c (.' oldprops :argv))))
 
-    :componentDidMount
+    :componentWillMount
     (fn []
       (this-as c
                (.! c :cljsMountOrder (batch/next-mount-count))
@@ -145,7 +145,7 @@
       (or wrap (default-wrapper f)))))
 
 (def obligatory {:shouldComponentUpdate nil
-                 :componentDidMount nil
+                 :componentWillMount nil
                  :componentWillUnmount nil})
 
 (def dash-to-camel (util/memoize-1 util/dash-to-camel))