diff --git a/exercises/ch-11-ex-1/authorizationServer.js b/exercises/ch-11-ex-1/authorizationServer.js
index be32b86b..b2c82f9b 100644
--- a/exercises/ch-11-ex-1/authorizationServer.js
+++ b/exercises/ch-11-ex-1/authorizationServer.js
@@ -247,28 +247,27 @@ app.post("/token", function(req, res){
             return;
         }
     } else if (req.body.grant_type == 'refresh_token') {
-        nosql.one(function(token) {
-            if (token.refresh_token == req.body.refresh_token) {
-                return token;
-            }
-        }, function(err, token) {
-            if (token) {
-                console.log("We found a matching refresh token: %s", req.body.refresh_token);
-                if (token.client_id != clientId) {
-                    nosql.remove(function(found) { return (found == token); }, function () {} );
+        nosql.one().make(builder => {
+            builder.where('refresh_token', req.body.refresh_token);
+            builder.callback(function(err, token) {
+                if (token) {
+                    console.log("We found a matching refresh token: %s", req.body.refresh_token);
+                    if (token.client_id != clientId) {
+                        nosql.remove(function(found) { return (found == token); }, function () {} );
+                        res.status(400).json({error: 'invalid_grant'});
+                        return;
+                    }
+                    var access_token = randomstring.generate();
+                    nosql.insert({ access_token: access_token, client_id: clientId });
+                    var token_response = { access_token: access_token, token_type: 'Bearer',  refresh_token: token.refresh_token };
+                    res.status(200).json(token_response);
+                    return;
+                } else {
+                    console.log('No matching token was found.');
                     res.status(400).json({error: 'invalid_grant'});
                     return;
                 }
-                var access_token = randomstring.generate();
-                nosql.insert({ access_token: access_token, client_id: clientId });
-                var token_response = { access_token: access_token, token_type: 'Bearer',  refresh_token: token.refresh_token };
-                res.status(200).json(token_response);
-                return;
-            } else {
-                console.log('No matching token was found.');
-                res.status(400).json({error: 'invalid_grant'});
-                return;
-            }
+            });
         });
     } else {
         console.log('Unknown grant type %s', req.body.grant_type);
@@ -315,4 +314,4 @@ var server = app.listen(9001, 'localhost', function () {
 
   console.log('OAuth Authorization Server is listening at http://%s:%s', host, port);
 });
- 
+
diff --git a/exercises/ch-11-ex-1/package.json b/exercises/ch-11-ex-1/package.json
index 28f0e5c5..be9d909d 100644
--- a/exercises/ch-11-ex-1/package.json
+++ b/exercises/ch-11-ex-1/package.json
@@ -9,7 +9,7 @@
     "consolidate": "^0.13.1",
     "qs": "^4.0.0",
     "randomstring": "^1.0.7",
-    "nosql": "^3.0.3",
+    "nosql": "^6.1.0",
     "base64url": "^1.0.4",
     "cors": "^2.7.1",
     "jsrsasign": "^5.0.0"