diff --git a/src/clj/commiteth/github/core.clj b/src/clj/commiteth/github/core.clj
index 84322ea..e4832cd 100644
--- a/src/clj/commiteth/github/core.clj
+++ b/src/clj/commiteth/github/core.clj
@@ -108,12 +108,12 @@
     (repos/delete-hook user repo hook-id (auth-params token))))
 
 (defn github-comment-hash
-  [user repo issue-number balance]
-  (digest/sha-256 (str "SALT_Yoh2looghie9jishah7aiphahphoo6udiju" user repo issue-number balance)))
+  [user repo issue-number]
+  (digest/sha-256 (str "SALT_Yoh2looghie9jishah7aiphahphoo6udiju" user repo issue-number)))
 
 (defn- get-qr-url
-  [user repo issue-number balance]
-  (let [hash (github-comment-hash user repo issue-number balance)]
+  [user repo issue-number]
+  (let [hash (github-comment-hash user repo issue-number)]
     (str (server-address) (format "/qr/%s/%s/bounty/%s/%s/qr.png" user repo issue-number hash))))
 
 (defn- md-url
@@ -127,15 +127,16 @@
   (str "!" (md-url alt src)))
 
 (defn generate-comment
-  [user repo issue-number balance]
-  (let [image-url (md-image "QR Code" (get-qr-url user repo issue-number balance))
+  [user repo issue-number contract-address balance]
+  (let [image-url (md-image "QR Code" (get-qr-url user repo issue-number))
         balance   (str balance " ETH")
         site-url  (md-url (server-address) (server-address))]
-    (format "Current balance: %s\n%s\n%s" balance image-url site-url)))
+    (format "Current balance: %s\nContract address: %s\n%s\n%s"
+            balance contract-address image-url site-url)))
 
 (defn post-comment
-  [user repo issue-number balance]
-  (let [comment (generate-comment user repo issue-number balance)]
+  [user repo issue-number contract-address balance]
+  (let [comment (generate-comment user repo issue-number contract-address balance)]
     (log/debug "Posting comment to" (str user "/" repo "/" issue-number) ":" comment)
     (issues/create-comment user repo issue-number comment (self-auth-params))))
 
@@ -158,8 +159,8 @@
     (assoc req :body (json/generate-string (or raw-query proper-query)))))
 
 (defn update-comment
-  [user repo comment-id issue-number balance]
-  (let [comment (generate-comment user repo issue-number balance)]
+  [user repo comment-id issue-number contract-address balance]
+  (let [comment (generate-comment user repo issue-number contract-address balance)]
     (log/debug (str "Updating " user "/" repo "/" issue-number
                     " comment #" comment-id " with contents: " comment))
     (let [req (make-patch-request "repos/%s/%s/issues/comments/%s"
diff --git a/src/clj/commiteth/routes/qrcodes.clj b/src/clj/commiteth/routes/qrcodes.clj
index 44296a4..6940ef1 100644
--- a/src/clj/commiteth/routes/qrcodes.clj
+++ b/src/clj/commiteth/routes/qrcodes.clj
@@ -33,7 +33,7 @@
   (context "/qr" []
            ;; user may be an organization here
            (GET "/:user/:repo/bounty/:issue{[0-9]{1,9}}/:hash/qr.png" [user repo issue hash]
-                (log/debug "qr PNG GET")
+                (log/debug "qr PNG GET" user repo issue hash)
                 (let [{address      :contract_address
                        login        :login
                        repo         :repo
@@ -45,8 +45,11 @@
                   (log/debug "address:" address "balance:" balance)
 
                   (if (and address
-                           (= hash (github/github-comment-hash user repo issue balance)))
-                    (let [issue-url (str login "/" repo "/issues/" issue-number)]
-                      (log/debug "balance:" address)
-                      (ok (generate-image address balance issue-url 768 256)))
+                           (= hash (github/github-comment-hash user repo issue)))
+                    (let [issue-url (str login "/" repo "/issues/" issue-number)
+                          image-url (generate-image address balance issue-url 768 256)
+                          response  (assoc-in (ok image-url)
+                                              [:headers "cache-control"] "no-cache")]
+                      (log/debug "balance:" address "response" response)
+                      response)
                     (bad-request))))))
diff --git a/src/clj/commiteth/scheduler.clj b/src/clj/commiteth/scheduler.clj
index 9731b0a..7d3c3e0 100644
--- a/src/clj/commiteth/scheduler.clj
+++ b/src/clj/commiteth/scheduler.clj
@@ -24,7 +24,11 @@
                repo         :repo
                issue-number :issue_number} issue
               balance (eth/get-balance-eth contract-address 4)
-              {comment-id :id} (github/post-comment user repo issue-number balance)]
+              {comment-id :id} (github/post-comment user
+                                                    repo
+                                                    issue-number
+                                                    contract-address
+                                                    balance)]
           (issues/update-comment-id issue-id comment-id))))))
 
 (defn self-sign-bounty
@@ -72,7 +76,12 @@
             current-balance-eth (eth/hex->eth current-balance-hex 8)]
         (when-not (= old-balance current-balance-hex)
           (issues/update-balance contract-address current-balance-hex)
-          (github/update-comment login repo comment-id issue-number current-balance-eth))))))
+          (github/update-comment login
+                                 repo
+                                 comment-id
+                                 issue-number
+                                 contract-address
+                                 current-balance-eth))))))
 
 (def scheduler-thread-name "SCHEDULER_THREAD")