diff --git a/src/klipse/klipse_editors.cljs b/src/klipse/klipse_editors.cljs
index 665653bc..f7de1d48 100644
--- a/src/klipse/klipse_editors.cljs
+++ b/src/klipse/klipse_editors.cljs
@@ -1,7 +1,7 @@
 (ns klipse.klipse-editors
   (:require-macros
    [gadjett.core :refer [dbg]]
-   [purnam.core :refer [!]]
+   [purnam.core :refer [! !>]]
    [cljs.core.async.macros :refer [go go-loop]])
   (:require
    [goog.dom :as gdom]
@@ -65,7 +65,16 @@
               (let [result (<! evaluation-chan)
                     results (str previous-results result)]
                 (when (some? result) ;exit if the channel is closed
-                  (setter results)
+                  (if (string? result)
+                    (setter results)
+                    (let [hasError (and (= (first result) :err))]
+                      (when hasError (setter (second result)))      ;; only report the :err messages for now
+                      (when-let [klipse-dom-node (js/document.querySelector ".klipse-container")]
+                         (let [event-payload (clj->js {:detail {:result result
+                                                                :hasError hasError
+                                                                :resultElement (:result-element @state)}})]
+                              (!> klipse-dom-node.dispatchEvent
+                                  (js/CustomEvent. "klipse-snippet-evaled" event-payload))))))
                   (recur results))))))
         (catch :default e
           (setter e))))))
@@ -102,7 +111,7 @@
 (s/def ::codemirror-options map?)
 (s/def ::editor-mode string?)
 
-(s/fdef editor-options 
+(s/fdef editor-options
         :args (s/cat :in-mode ::editor-mode
                      :out-mode ::editor-mode
                      :options-in ::codemirror-options
diff --git a/src/klipse/lang/python.cljs b/src/klipse/lang/python.cljs
index 744cf9e2..ff6bc79b 100644
--- a/src/klipse/lang/python.cljs
+++ b/src/klipse/lang/python.cljs
@@ -22,17 +22,17 @@
   (init)
   (let [c (chan)]
     (!> js/Sk.configure #js {:output #(put! c %)
-                             :read builtin-read })
-    (-> 
+                             :read   builtin-read})
+    (->
       (!> js/Sk.misceval.asyncToPromise
           (fn []
             (put! c "Output:\n")
             (! js/Sk.TurtleGraphics.target container-id)
             (!> js/Sk.importMainWithBody "<stdin>" false exp true)))
       (.then (fn [mod]
-               (!> js/console.info "success to eval skulpt: "))
+               (put! c [:ok mod]))
              (fn [err]
-               (put! c (str "error: " err)))))
+               (put! c [:err (str "error:\n" err)]))))
     c))
 
 (def opts {:editor-in-mode "python"