diff --git a/.gitignore b/.gitignore
index 5afd8e3..9253f06 100644
--- a/.gitignore
+++ b/.gitignore
@@ -28,3 +28,5 @@ node_modules
 .idea/
 .coverrun
 reports/
+.coverdata/
+debug/
diff --git a/README.md b/README.md
index a54c452..da67eab 100644
--- a/README.md
+++ b/README.md
@@ -8,11 +8,13 @@ Experimental/Unstable
 
 ```js
 var graphite = require('graphite-promise'),
-client = graphite.createClient(<Graphite URL>);
+client = graphite.createClient(<graphite-url e.g 'plaintext://127.0.0.1:2003/'>);
 client.write(metric, timestamp)
   .then(function(){})
   .catch(function(reason){})
-  .finally(function(){});
+  .finally(function(){
+    client.end();
+  });
 ```
 ### Example
 
diff --git a/lib/carbon.js b/lib/carbon.js
index a1706b1..146cf3b 100644
--- a/lib/carbon.js
+++ b/lib/carbon.js
@@ -4,57 +4,53 @@ var RSVP = require('rsvp'),
 
 function CarbonClient (properties) {
     properties = properties || {};
-    this._dsn = properties.dsn;
+    this._url = properties.url;
     this._socket = properties.socket || null;
 }
 
 CarbonClient.prototype.write = function (metrics, timestamp) {
     var self = this;
-    self._lazyConnect().then(function () {
-    });
     return new RSVP.Promise(function (resolve, reject) {
-        var lines = '';
-        for (var path in metrics) {
-            if (metrics.hasOwnProperty(path)) {
-                var value = metrics[path];
-                lines += [path, value, timestamp].join(' ') + '\n';
+        self._connect().then(function (socket) {
+            var lines = '';
+            for (var path in metrics) {
+                if (metrics.hasOwnProperty(path)) {
+                    var value = metrics[path];
+                    lines += [path, value, timestamp].join(' ') + '\n';
+                }
             }
-        }
-
-        self._socket.write(lines, 'utf-8', function (err) {
-            if (err) {
-                reject(err);
-            } else {
-                resolve(metrics);
-            }
-        });
+            socket.write(lines, 'utf-8', function (err) {
+                return err && reject(err) || resolve(lines);
+            });
+        }).catch(reject);
     });
 };
 
-CarbonClient.prototype._lazyConnect = function () {
+CarbonClient.prototype._connect = function () {
     var self = this;
     return new RSVP.Promise(function (resolve, reject) {
         if (self._socket) {
-            return resolve();
+            return resolve(self._socket);
         }
-        var dsn = url.parse(self._dsn),
+        var dsn = url.parse(self._url),
             port = parseInt(dsn.port, 10) || 2003,
             host = dsn.hostname,
             socket = new net.Socket();
         self._socket = socket.connect(port, host, 1000, function (err) {
-            if (err) {
-                reject(err);
-            } else {
-                resolve();
-            }
+            return err && reject(err) || resolve(self._socket);
         });
     });
 };
 
 CarbonClient.prototype.end = function () {
-    if (this._socket) {
-        this._socket.end();
-    }
+    return new RSVP.Promise(function (resolve, reject) {
+        try {
+            resolve(this._socket && this._socket.end());
+        }
+        catch (err) {
+            reject(err);
+        }
+    });
 };
 
 module.exports = CarbonClient;
diff --git a/lib/graphite.js b/lib/graphite.js
index f8355b7..30e4615 100644
--- a/lib/graphite.js
+++ b/lib/graphite.js
@@ -1,4 +1,5 @@
-var CarbonClient = require('./carbon');
+var client = require('./carbon'),
+    metric = require('./metric');
 
 function GraphiteClient (properties) {
     this._carbon = properties.carbon;
@@ -6,36 +7,28 @@ function GraphiteClient (properties) {
 
 GraphiteClient.createClient = function (carbonDsn) {
     return new this({
-        carbon: new CarbonClient({dsn: carbonDsn})
+        carbon: new client({url: carbonDsn})
     });
 };
 
-GraphiteClient.flatten = function (obj, flat, prefix) {
-    flat = flat || {};
-    prefix = prefix || '';
-
-    for (var key in obj) {
-        if (obj.hasOwnProperty(key)) {
-            var value = obj[key];
-            if (typeof value === 'object') {
-                this.flatten(value, flat, prefix + key + '.');
-            } else {
-                flat[prefix + key] = value;
-            }
-        }
-    }
-
-    return flat;
-};
-
+/**
+ * Writes metric with timestamp to Graphite
+ *
+ * @param metrics an object with values, e.g. {home:{indoor:{temp:21.2}}}
+ * @param timestamp defaults to Date.now()
+ * @returns {RSVP.Promise} a promise
+ */
 GraphiteClient.prototype.write = function (metrics, timestamp) {
     timestamp = timestamp || Date.now();
     timestamp = Math.floor(timestamp / 1000);
-    return this._carbon.write(GraphiteClient.flatten(metrics), timestamp);
+    return this._carbon.write(metric.flatten(metrics), timestamp);
 };
 
+/**
+ * Ends the connection
+ */
 GraphiteClient.prototype.end = function () {
-    this._carbon.end();
+    return this._carbon.end();
 };
 
 module.exports = GraphiteClient;
diff --git a/lib/metric.js b/lib/metric.js
new file mode 100644
index 0000000..f1bea83
--- /dev/null
+++ b/lib/metric.js
@@ -0,0 +1,18 @@
+module.exports = {
+    flatten: function (obj, flat, prefix) {
+        flat = flat || {};
+        prefix = prefix || '';
+
+        for (var key in obj) {
+            if (obj.hasOwnProperty(key)) {
+                var value = obj[key];
+                if (typeof value === 'object') {
+                    this.flatten(value, flat, prefix + key + '.');
+                } else {
+                    flat[prefix + key] = value;
+                }
+            }
+        }
+        return flat;
+    }
+};
diff --git a/package.json b/package.json
index b147bfc..19b7d5c 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "graphite-promise",
-  "version": "0.0.1",
+  "version": "0.0.2",
   "description": "A node.js module to interface with Graphite promise style",
   "main": "./lib/graphite",
   "directories": {
diff --git a/test/carbon.js b/test/carbon.js
index e69de29..3c85a36 100644
--- a/test/carbon.js
+++ b/test/carbon.js
@@ -0,0 +1,37 @@
+/*jshint undef:false */
+var chaiAsPromised = require('chai-as-promised'),
+    chai = require('chai');
+
+chai.should();
+chai.use(chaiAsPromised);
+
+describe('CarbonClient', function () {
+    var Carbon = require('./../lib/carbon'),
+        client = new Carbon({dsn: 'plaintext://127.0.0.1:2003/'}),
+        socketMock = {};
+
+    describe('#write', function () {
+        before(function () {
+            client._socket = socketMock;
+        });
+
+        it('writes flattened metrics encoded as utf-8', function (done) {
+            var metric = {'home.indoor.temp': 21.2},
+                timestamp = 1427727486200;
+            socketMock.write = function (lines, encoding, cb) {
+                lines.should.equal('home.indoor.temp 21.2 1427727486200\n');
+                encoding.should.equal('utf-8');
+                cb();
+            };
+            client.write(metric, timestamp).should.eventually.equal('home.indoor.temp 21.2 1427727486200\n').notify(done);
+        });
+        it('rejects when a socket error occur', function (done) {
+            var metric = {'home.indoor.temp': 21.2},
+                timestamp = 1427727486200;
+            socketMock.write = function (lines, encoding, cb) {
+                cb(new Error('fail'));
+            };
+            client.write(metric, timestamp).should.eventually.be.rejected.notify(done);
+        });
+    });
+});
diff --git a/test/graphite.js b/test/graphite.js
index e92d13a..0cd7bc6 100644
--- a/test/graphite.js
+++ b/test/graphite.js
@@ -6,6 +6,11 @@ chai.should();
 chai.use(chaiAsPromised);
 
 describe('GraphiteClient', function () {
-    describe('#write', function () {
+    describe('#end', function () {
+        it('should be safe to call any time', function (done) {
+            var graphite = require('./../lib/graphite'),
+                client = graphite.createClient('plaintext://127.0.0.1:2003/');
+            client.end().should.be.fulfilled.notify(done);
+        });
     });
 });
diff --git a/test/index.js b/test/index.js
index 8756e4e..b0b5675 100644
--- a/test/index.js
+++ b/test/index.js
@@ -1,2 +1,3 @@
 require('./carbon');
-require('./graphite');
\ No newline at end of file
+require('./graphite');
+require('./metric');
\ No newline at end of file
diff --git a/test/metric.js b/test/metric.js
new file mode 100644
index 0000000..fd9c94c
--- /dev/null
+++ b/test/metric.js
@@ -0,0 +1,29 @@
+/*jshint undef:false */
+var chaiAsPromised = require('chai-as-promised'),
+    chai = require('chai'),
+    metric = require('./../lib/metric');
+
+chai.should();
+chai.use(chaiAsPromised);
+
+describe('metric', function () {
+    describe('#flatten', function () {
+        it('flattens objects', function () {
+            metric.flatten({home: {indoor: {temp: 21.2}}}).should.deep.equal({'home.indoor.temp': 21.2});
+        });
+        it('flattens objects two properties', function () {
+            metric.flatten({home: {indoor: {temp: 21.2, humidity: 94.5}}})
+                .should.deep.equal({'home.indoor.humidity': 94.5, 'home.indoor.temp': 21.2});
+        });
+        it('flattens objects three properties', function () {
+            metric.flatten({foz: {baz: {foo: 42, bar: 1337, soz: 101}}})
+                .should.deep.equal({'foz.baz.bar': 1337, 'foz.baz.foo': 42, 'foz.baz.soz': 101});
+        });
+        it('handles empty objects', function () {
+            metric.flatten({}).should.deep.equal({});
+        });
+        it('handles shallow objects', function () {
+            metric.flatten({temp: 27.1}).should.deep.equal({temp: 27.1});
+        });
+    });
+});