diff --git a/index.js b/index.js
index d74cbd6..8cffd37 100644
--- a/index.js
+++ b/index.js
@@ -26,7 +26,59 @@ module.exports.create = function (defaults) {
       cb(null);
     }
 
+  , loopback: function (defaults, domain, challenge, done) {
+      var hostname = domain + (defaults.loopbackPort ? ':' + defaults.loopbackPort : '');
+      var urlstr = 'http://' + hostname + '/.well-known/acme-challenge/' + key;
+
+      require('http').get(urlstr, function (res) {
+        if (200 !== res.statusCode) {
+          done(new Error("local loopback failed with statusCode " + res.statusCode));
+          return;
+        }
+        var chunks = [];
+        res.on('data', function (chunk) {
+          chunks.push(chunk);
+        });
+        res.on('end', function () {
+          var str = Buffer.concat(chunks).toString('utf8').trim();
+          done(null, str);
+        });
+      }).setTimeout(defaults.loopbackTimeout, function () {
+        done(new Error("loopback timeout, could not reach server"));
+      }).on('error', function (err) {
+        done(err);
+      });
+    }
+
+  , test: function (args, domain, challenge, keyAuthorization, done) {
+      var me = this;
+      var key = keyAuthorization || challenge;
+
+      me.set(args, domain, challenge, key, function (err) {
+        if (err) { done(err); return; }
+
+        myDefaults.loopbackPort = args.loopbackPort;
+        myDefaults.webrootPath = args.webrootPath;
+        me.loopback(args, domain, challenge, function (err, _key) {
+          if (err) { done(err); return; }
+
+          if (key !== _key) {
+            err = new Error("keyAuthorization [original] '" + key + "'"
+              + " did not match [result] '" + _key + "'");
+            return;
+          }
+
+          me.remove(myDefaults, domain, challenge, function (_err) {
+            if (_err) { done(_err); return; }
+
+            done(err);
+          });
+        });
+      });
+    }
+
   };
 
+
   return handlers;
 };
diff --git a/package.json b/package.json
index 7075987..694bd19 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "le-challenge-standalone",
-  "version": "2.0.1",
+  "version": "2.1.1",
   "description": "An in-memory strategy for node-letsencrypt for setting, retrieving, and clearing ACME challenges issued by the ACME server.",
   "homepage": "https://greenlock.domains/",
   "main": "index.js",