diff --git a/composer.json b/composer.json
index ca84d93..3fa7163 100644
--- a/composer.json
+++ b/composer.json
@@ -32,7 +32,8 @@
         "okitsu/zabbix-sender": "*@dev",
         "symfony/config": "~2.3",
         "symfony/dependency-injection": "~2.3",
-        "symfony/http-kernel": "~2.3"
+        "symfony/http-kernel": "~2.3",
+        "phpunit/phpunit": "4.5.0"
     },
     "autoload": {
         "psr-4": {
diff --git a/src/Beberlei/Bundle/MetricsBundle/BeberleiMetricsBundle.php b/src/Beberlei/Bundle/MetricsBundle/BeberleiMetricsBundle.php
index 579a346..8eba1a6 100644
--- a/src/Beberlei/Bundle/MetricsBundle/BeberleiMetricsBundle.php
+++ b/src/Beberlei/Bundle/MetricsBundle/BeberleiMetricsBundle.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Bundle\MetricsBundle;
 
 use Symfony\Component\HttpKernel\Bundle\Bundle;
diff --git a/src/Beberlei/Bundle/MetricsBundle/DependencyInjection/BeberleiMetricsExtension.php b/src/Beberlei/Bundle/MetricsBundle/DependencyInjection/BeberleiMetricsExtension.php
index c8ba150..0bfef52 100644
--- a/src/Beberlei/Bundle/MetricsBundle/DependencyInjection/BeberleiMetricsExtension.php
+++ b/src/Beberlei/Bundle/MetricsBundle/DependencyInjection/BeberleiMetricsExtension.php
@@ -78,6 +78,7 @@ private function createCollector($type, $config)
                 return $definition;
             case 'logger':
             case 'null':
+            case 'memory':
                 return $definition;
             case 'prometheus':
                 $definition->replaceArgument(0, new Reference($config['prometheus_collector_registry']));
diff --git a/src/Beberlei/Bundle/MetricsBundle/Resources/config/metrics.xml b/src/Beberlei/Bundle/MetricsBundle/Resources/config/metrics.xml
index b383fdd..128fd63 100644
--- a/src/Beberlei/Bundle/MetricsBundle/Resources/config/metrics.xml
+++ b/src/Beberlei/Bundle/MetricsBundle/Resources/config/metrics.xml
@@ -60,6 +60,8 @@
             <argument /> <!-- sender, set by the extension -->
             <argument /> <!-- host, set by the extension -->
         </service>
+        <service id="beberlei_metrics.collector_proto.memory" class="Beberlei\Metrics\Collector\InMemory" abstract="true">
+        </service>
     </services>
 
 </container>
diff --git a/src/Beberlei/Bundle/MetricsBundle/Tests/DependencyInjection/BeberleiMetricsExtensionTest.php b/src/Beberlei/Bundle/MetricsBundle/Tests/DependencyInjection/BeberleiMetricsExtensionTest.php
index c9d6700..2138fc4 100644
--- a/src/Beberlei/Bundle/MetricsBundle/Tests/DependencyInjection/BeberleiMetricsExtensionTest.php
+++ b/src/Beberlei/Bundle/MetricsBundle/Tests/DependencyInjection/BeberleiMetricsExtensionTest.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Bundle\MetricsBundle\Tests\DependencyInjection;
 
 use Symfony\Component\DependencyInjection\ContainerBuilder;
@@ -49,7 +50,7 @@ public function testWithGraphite()
     }
 
     /**
-     * @expectedException Symfony\Component\Config\Definition\Exception\InvalidConfigurationException
+     * @expectedException \Symfony\Component\Config\Definition\Exception\InvalidConfigurationException
      * The source has to be specified to use a Librato
      */
     public function testWithLibratoAndInvalidConfiguration()
@@ -206,7 +207,7 @@ public function testWithTelegraf()
         $this->assertSame(1234, $this->getProperty($collector, 'port'));
         $this->assertSame('application.com.symfony.', $this->getProperty($collector, 'prefix'));
 
-        $this->assertEquals(',string_tag=first_value,int_tag=123', $this->getProperty($collector, 'tags'));
+        $this->assertEquals($expectedTags, $this->getProperty($collector, 'tags'));
     }
 
     public function testWithZabbix()
@@ -330,6 +331,19 @@ public function testWithPrometheus()
         $this->assertSame('', $this->getProperty($collector, 'namespace'));
     }
 
+    public function testWithInMemory()
+    {
+        $container = $this->createContainer(array(
+            'collectors' => array(
+                'memory' => array(
+                    'type' => 'memory',
+                ),
+            ),
+        ));
+        $collector = $container->get('beberlei_metrics.collector.memory');
+        $this->assertInstanceOf('Beberlei\Metrics\Collector\InMemory', $collector);
+    }
+
     public function testWithPrometheusAndWithNamespace()
     {
         $expectedNamespace = 'some_namespace';
diff --git a/src/Beberlei/Metrics/Collector/Collector.php b/src/Beberlei/Metrics/Collector/Collector.php
index 4e7179b..51d44a0 100644
--- a/src/Beberlei/Metrics/Collector/Collector.php
+++ b/src/Beberlei/Metrics/Collector/Collector.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Collector;
 
 /**
diff --git a/src/Beberlei/Metrics/Collector/DoctrineDBAL.php b/src/Beberlei/Metrics/Collector/DoctrineDBAL.php
index 83e0b56..33ac0f6 100644
--- a/src/Beberlei/Metrics/Collector/DoctrineDBAL.php
+++ b/src/Beberlei/Metrics/Collector/DoctrineDBAL.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Collector;
 
 use Doctrine\DBAL\Connection;
diff --git a/src/Beberlei/Metrics/Collector/DogStatsD.php b/src/Beberlei/Metrics/Collector/DogStatsD.php
old mode 100644
new mode 100755
index 1207239..925dfde
--- a/src/Beberlei/Metrics/Collector/DogStatsD.php
+++ b/src/Beberlei/Metrics/Collector/DogStatsD.php
@@ -10,9 +10,10 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Collector;
 
-class DogStatsD implements Collector, InlineTaggableGaugeableCollector
+class DogStatsD implements Collector, TaggableCollector, TaggableGaugeableCollector, InlineTaggableGaugeableCollector
 {
     /** @var string */
     private $host;
@@ -26,6 +27,9 @@ class DogStatsD implements Collector, InlineTaggableGaugeableCollector
     /** @var array */
     private $data;
 
+    /** @var array */
+    private $tags = array();
+
     /**
      * @param string $host
      * @param string $port
@@ -105,6 +109,14 @@ public function flush()
         $this->data = array();
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function setTags($tags)
+    {
+        $this->tags = $tags;
+    }
+
     /**
      * Given a key/value map of metric tags, builds them into a
      * DogStatsD tag string and returns the string.
@@ -117,6 +129,8 @@ private function buildTagString($tags)
     {
         $results = array();
 
+        $tags = array_merge($this->tags, $tags);
+
         foreach ($tags as $key => $value) {
             $results[] = sprintf('%s:%s', $key, $value);
         }
diff --git a/src/Beberlei/Metrics/Collector/GaugeableCollector.php b/src/Beberlei/Metrics/Collector/GaugeableCollector.php
index 68446aa..ffeb98f 100644
--- a/src/Beberlei/Metrics/Collector/GaugeableCollector.php
+++ b/src/Beberlei/Metrics/Collector/GaugeableCollector.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Collector;
 
 interface GaugeableCollector
diff --git a/src/Beberlei/Metrics/Collector/Graphite.php b/src/Beberlei/Metrics/Collector/Graphite.php
index 1714b62..e052565 100644
--- a/src/Beberlei/Metrics/Collector/Graphite.php
+++ b/src/Beberlei/Metrics/Collector/Graphite.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Collector;
 
 use Exception;
diff --git a/src/Beberlei/Metrics/Collector/InMemory.php b/src/Beberlei/Metrics/Collector/InMemory.php
new file mode 100644
index 0000000..95df43b
--- /dev/null
+++ b/src/Beberlei/Metrics/Collector/InMemory.php
@@ -0,0 +1,154 @@
+<?php
+/**
+ * Beberlei Metrics.
+ *
+ * LICENSE
+ *
+ * This source file is subject to the MIT license that is bundled
+ * with this package in the file LICENSE.txt.
+ * If you did not receive a copy of the license and are unable to
+ * obtain it through the world-wide-web, please send an email
+ * to kontakt@beberlei.de so I can send you a copy immediately.
+ */
+
+namespace Beberlei\Metrics\Collector;
+
+/**
+ * Stores metrics in memory.
+ * Useful for testing and with any custom persistence mechanisms.
+ */
+class InMemory implements Collector, GaugeableCollector
+{
+    /** @var int[] */
+    private $incrementData = [];
+    /** @var int[] */
+    private $gaugeData = [];
+    /** @var int[] */
+    private $timingData = [];
+
+    /**
+     * Updates a counter by some arbitrary amount.
+     *
+     * @param string $variable
+     * @param int    $value    The amount to increment the counter by
+     */
+    public function measure($variable, $value)
+    {
+        if (!isset($this->incrementData[$variable])) {
+            $this->incrementData[$variable] = 0;
+        }
+        $this->incrementData[$variable] += $value;
+    }
+
+    /**
+     * Increments a counter.
+     *
+     * @param string $variable
+     */
+    public function increment($variable)
+    {
+        $this->measure($variable, 1);
+    }
+
+    /**
+     * Decrements a counter.
+     *
+     * @param string $variable
+     */
+    public function decrement($variable)
+    {
+        $this->measure($variable, -1);
+    }
+
+    /**
+     * Records a timing.
+     *
+     * @param string $variable
+     * @param int    $time     The duration of the timing in milliseconds
+     */
+    public function timing($variable, $time)
+    {
+        if (!isset($this->timingData[$variable])) {
+            $this->timingData[$variable] = 0;
+        }
+        $this->timingData[$variable] = $time;
+    }
+
+    /**
+     * Sends the metrics to the adapter backend.
+     */
+    public function flush()
+    {
+        $this->timingData = [];
+        $this->gaugeData = [];
+        $this->incrementData = [];
+    }
+
+    /**
+     * Updates a gauge by an arbitrary amount.
+     *
+     * @param string $variable
+     * @param int    $value
+     */
+    public function gauge($variable, $value)
+    {
+        $sign = substr($value, 0, 1);
+
+        if (in_array($sign, ['-', '+'])) {
+            $this->gaugeIncrement($variable, (int) $value);
+
+            return;
+        }
+
+        $this->gaugeData[$variable] = $value;
+    }
+
+    /**
+     * Returns current value of incremented/decremented/measured variable.
+     *
+     * @param string $variable
+     *
+     * @return int
+     */
+    public function getMeasure($variable)
+    {
+        return isset($this->incrementData[$variable]) ? $this->incrementData[$variable] : 0;
+    }
+
+    /**
+     * Returns current value of gauged variable.
+     *
+     * @param string $variable
+     *
+     * @return int
+     */
+    public function getGauge($variable)
+    {
+        return isset($this->gaugeData[$variable]) ? $this->gaugeData[$variable] : 0;
+    }
+
+    /**
+     * Returns current value of timed variable.
+     *
+     * @param string $variable
+     *
+     * @return int
+     */
+    public function getTiming($variable)
+    {
+        return isset($this->timingData[$variable]) ? $this->timingData[$variable] : 0;
+    }
+
+    /**
+     * @param string $variable
+     * @param int    $value
+     */
+    private function gaugeIncrement($variable, $value)
+    {
+        if (!isset($this->gaugeData[$variable])) {
+            $this->gaugeData[$variable] = 0;
+        }
+
+        $this->gaugeData[$variable] += $value;
+    }
+}
diff --git a/src/Beberlei/Metrics/Collector/InfluxDB.php b/src/Beberlei/Metrics/Collector/InfluxDB.php
old mode 100644
new mode 100755
index 67768cd..dca72e8
--- a/src/Beberlei/Metrics/Collector/InfluxDB.php
+++ b/src/Beberlei/Metrics/Collector/InfluxDB.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Collector;
 
 use InfluxDB\Client;
@@ -36,33 +37,33 @@ public function __construct(Client $client)
     /**
      * {@inheritdoc}
      */
-    public function increment($variable)
+    public function increment($variable, $tags = array())
     {
-        $this->data[] = array($variable, 1);
+        $this->data[] = array($variable, 1, $tags);
     }
 
     /**
      * {@inheritdoc}
      */
-    public function decrement($variable)
+    public function decrement($variable, $tags = array())
     {
-        $this->data[] = array($variable, -1);
+        $this->data[] = array($variable, -1, $tags);
     }
 
     /**
      * {@inheritdoc}
      */
-    public function timing($variable, $time)
+    public function timing($variable, $time, $tags = array())
     {
-        $this->data[] = array($variable, $time);
+        $this->data[] = array($variable, $time, $tags);
     }
 
     /**
      * {@inheritdoc}
      */
-    public function measure($variable, $value)
+    public function measure($variable, $value, $tags = array())
     {
-        $this->data[] = array($variable, $value);
+        $this->data[] = array($variable, $value, $tags);
     }
 
     /**
@@ -78,7 +79,7 @@ public function flush()
                         'fields' => array('value' => $data[1]),
                     ),
                 ),
-                'tags' => $this->tags,
+                'tags' => array_merge($this->tags, $data[2]),
             ));
         }
 
diff --git a/src/Beberlei/Metrics/Collector/InlineTaggableGaugeableCollector.php b/src/Beberlei/Metrics/Collector/InlineTaggableGaugeableCollector.php
index 3873cec..d250d30 100644
--- a/src/Beberlei/Metrics/Collector/InlineTaggableGaugeableCollector.php
+++ b/src/Beberlei/Metrics/Collector/InlineTaggableGaugeableCollector.php
@@ -10,10 +10,12 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Collector;
 
 /**
  * InlineTaggableGaugeableCollector interface.
+ * @deprecated Replaced by TaggableCollector + TaggableGaugeableCollector
  */
 interface InlineTaggableGaugeableCollector
 {
diff --git a/src/Beberlei/Metrics/Collector/Librato.php b/src/Beberlei/Metrics/Collector/Librato.php
index 53502ce..9bbd96d 100644
--- a/src/Beberlei/Metrics/Collector/Librato.php
+++ b/src/Beberlei/Metrics/Collector/Librato.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Collector;
 
 use Buzz\Browser;
diff --git a/src/Beberlei/Metrics/Collector/Logger.php b/src/Beberlei/Metrics/Collector/Logger.php
index aa689c7..c501981 100644
--- a/src/Beberlei/Metrics/Collector/Logger.php
+++ b/src/Beberlei/Metrics/Collector/Logger.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Collector;
 
 use Psr\Log\LoggerInterface;
diff --git a/src/Beberlei/Metrics/Collector/Null.php b/src/Beberlei/Metrics/Collector/Null.php
index 76d531a..f651dc8 100644
--- a/src/Beberlei/Metrics/Collector/Null.php
+++ b/src/Beberlei/Metrics/Collector/Null.php
@@ -1,6 +1,6 @@
 <?php
 /**
- * Beberlei Metrics
+ * Beberlei Metrics.
  *
  * LICENSE
  *
@@ -14,7 +14,7 @@
 namespace Beberlei\Metrics\Collector;
 
 /**
- * @deprecated for PHP7 compatibility, use NullCollector instead.
+ * @deprecated for PHP7 compatibility, use NullCollector instead
  */
 class Null extends NullCollector
 {
diff --git a/src/Beberlei/Metrics/Collector/NullCollector.php b/src/Beberlei/Metrics/Collector/NullCollector.php
index 961556c..acb543b 100644
--- a/src/Beberlei/Metrics/Collector/NullCollector.php
+++ b/src/Beberlei/Metrics/Collector/NullCollector.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Collector;
 
 class NullCollector implements Collector, GaugeableCollector
diff --git a/src/Beberlei/Metrics/Collector/Prometheus.php b/src/Beberlei/Metrics/Collector/Prometheus.php
old mode 100644
new mode 100755
index ef36d3d..fad46ba
--- a/src/Beberlei/Metrics/Collector/Prometheus.php
+++ b/src/Beberlei/Metrics/Collector/Prometheus.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Collector;
 
 use Prometheus\CollectorRegistry;
@@ -51,42 +52,45 @@ public function __construct(CollectorRegistry $collectorRegistry, $namespace = '
     /**
      * {@inheritdoc}
      */
-    public function measure($variable, $value)
+    public function measure($variable, $value, $tags = array())
     {
         $this->data['gauges'][] = array(
             'name' => $variable,
             'value' => $value,
+            'tags' => $tags,
         );
     }
 
     /**
      * {@inheritdoc}
      */
-    public function increment($variable)
+    public function increment($variable, $tags = array())
     {
         $this->data['counters'][] = array(
             'name' => $variable,
             'value' => 1,
+			'tags' => $tags,
         );
     }
 
     /**
      * {@inheritdoc}
      */
-    public function decrement($variable)
+    public function decrement($variable, $tags = array())
     {
         $this->data['counters'][] = array(
             'name' => $variable,
             'value' => -1,
+			'tags' => $tags,
         );
     }
 
     /**
      * {@inheritdoc}
      */
-    public function timing($variable, $time)
+    public function timing($variable, $time, $tags = array())
     {
-        $this->measure($variable, $time);
+        $this->measure($variable, $time, $tags);
     }
 
     /**
@@ -98,22 +102,20 @@ public function flush()
             return;
         }
 
-        $tagsValues = array_values($this->tags);
-
         foreach ($this->data['counters'] as $counterData) {
-            $gauge = $this->getOrRegisterGaugeForVariable($counterData['name']);
+			$gauge = $this->getOrRegisterGaugeForVariable($counterData['name'], $counterData['tags']);
 
             if ($counterData['value'] > 0) {
-                $gauge->inc($tagsValues);
+                $gauge->inc(array_values(array_merge($this->tags, $counterData['tags'])));
             } elseif ($counterData['value'] < 0) {
-                $gauge->dec($tagsValues);
+                $gauge->dec(array_values(array_merge($this->tags, $counterData['tags'])));
             }
         }
 
         foreach ($this->data['gauges'] as $gaugeData) {
-            $gauge = $this->getOrRegisterGaugeForVariable($gaugeData['name']);
+			$gauge = $this->getOrRegisterGaugeForVariable($gaugeData['name'], $gaugeData['tags']);
 
-            $gauge->set($gaugeData['value'], $tagsValues);
+            $gauge->set($gaugeData['value'], array_values(array_merge($this->tags, $gaugeData['tags'])));
         }
 
         $this->data = array('counters' => array(), 'gauges' => array());
@@ -130,9 +132,10 @@ public function setTags($tags)
     /**
      * @param string $variable
      *
+     * @param array $tags
      * @return \Prometheus\Gauge
      */
-    private function getOrRegisterGaugeForVariable($variable)
+    private function getOrRegisterGaugeForVariable($variable, $tags = array())
     {
         try {
             $gauge = $this->collectorRegistry->getGauge($this->namespace, $variable);
@@ -141,7 +144,7 @@ private function getOrRegisterGaugeForVariable($variable)
                 $this->namespace,
                 $variable,
                 '',
-                array_keys($this->tags)
+                array_keys(array_merge($this->tags, $tags))
             );
         }
 
diff --git a/src/Beberlei/Metrics/Collector/StatsD.php b/src/Beberlei/Metrics/Collector/StatsD.php
index f3369ed..e6c92fc 100644
--- a/src/Beberlei/Metrics/Collector/StatsD.php
+++ b/src/Beberlei/Metrics/Collector/StatsD.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Collector;
 
 /**
diff --git a/src/Beberlei/Metrics/Collector/TaggableCollector.php b/src/Beberlei/Metrics/Collector/TaggableCollector.php
index 6ff2057..17fd969 100644
--- a/src/Beberlei/Metrics/Collector/TaggableCollector.php
+++ b/src/Beberlei/Metrics/Collector/TaggableCollector.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Collector;
 
 /**
@@ -23,4 +24,40 @@ interface TaggableCollector
      * @param array $tags
      */
     public function setTags($tags);
+
+	/**
+     * Updates a counter by some arbitrary amount.
+     *
+     * @param string $variable
+     * @param int    $value    The amount to increment the counter by
+     * @param array  $tags     Tags to be attached to the metric
+     *
+     * @return
+     */
+    public function measure($variable, $value, $tags = array());
+
+    /**
+     * Increments a counter.
+     *
+     * @param string $variable
+     * @param array  $tags     Tags to be attached to the metric
+     */
+    public function increment($variable, $tags = array());
+
+    /**
+     * Decrements a counter.
+     *
+     * @param string $variable
+     * @param array  $tags     Tags to be attached to the metric
+     */
+    public function decrement($variable, $tags = array());
+
+    /**
+     * Records a timing.
+     *
+     * @param string $variable
+     * @param int    $time     The duration of the timing in milliseconds
+     * @param array  $tags     Tags to be attached to the metric
+     */
+    public function timing($variable, $time, $tags = array());
 }
diff --git a/src/Beberlei/Metrics/Collector/TaggableGaugeableCollector.php b/src/Beberlei/Metrics/Collector/TaggableGaugeableCollector.php
new file mode 100755
index 0000000..189f1a6
--- /dev/null
+++ b/src/Beberlei/Metrics/Collector/TaggableGaugeableCollector.php
@@ -0,0 +1,28 @@
+<?php
+/**
+ * Beberlei Metrics.
+ *
+ * LICENSE
+ *
+ * This source file is subject to the MIT license that is bundled
+ * with this package in the file LICENSE.txt.
+ * If you did not receive a copy of the license and are unable to
+ * obtain it through the world-wide-web, please send an email
+ * to kontakt@beberlei.de so I can send you a copy immediately.
+ */
+namespace Beberlei\Metrics\Collector;
+
+/**
+ * TaggableGaugeableCollector interface.
+ */
+interface TaggableGaugeableCollector
+{
+    /**
+     * Updates a gauge by an arbitrary amount.
+     *
+     * @param string $variable
+     * @param int    $value
+     * @param array  $tags     Tags to be attached to the metric
+     */
+    public function gauge($variable, $value, $tags = array());
+}
diff --git a/src/Beberlei/Metrics/Collector/Telegraf.php b/src/Beberlei/Metrics/Collector/Telegraf.php
old mode 100644
new mode 100755
index a2ee1e4..67be04a
--- a/src/Beberlei/Metrics/Collector/Telegraf.php
+++ b/src/Beberlei/Metrics/Collector/Telegraf.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Collector;
 
 /**
@@ -17,7 +18,7 @@
  * ad hoc implementation for the StatsD - Telegraf integration,
  * support tagging.
  */
-class Telegraf implements Collector, GaugeableCollector, TaggableCollector
+class Telegraf implements Collector, TaggableCollector, TaggableGaugeableCollector, InlineTaggableGaugeableCollector
 {
     /** @var string */
     private $host;
@@ -31,8 +32,8 @@ class Telegraf implements Collector, GaugeableCollector, TaggableCollector
     /** @var array */
     private $data;
 
-    /** @var string */
-    private $tags = '';
+    /** @var array */
+    private $tags;
 
     /**
      * @param string $host
@@ -52,57 +53,57 @@ public function __construct($host = 'localhost', $port = '8125', $prefix = '')
      */
     public function setTags($tags)
     {
-        $this->tags = http_build_query($tags, '', ',');
-        $this->tags = (strlen($this->tags) > 0 ? ','.$this->tags : $this->tags);
-    }
+        $this->tags = $tags;
+	}
 
     /**
      * {@inheritdoc}
      */
-    public function timing($variable, $time)
+    public function timing($variable, $time, $tags = array())
     {
-        $this->data[] = sprintf('%s%s:%s|ms', $variable, $this->tags, $time);
+        $this->data[] = sprintf('%s%s:%s|ms', $variable, $this->buildTagString(array_merge($this->tags, $tags)), $time);
     }
 
     /**
      * {@inheritdoc}
      */
-    public function increment($variable)
+    public function increment($variable, $tags = array())
     {
-        $this->data[] = $variable.$this->tags.':1|c';
+        $this->data[] = $variable.$this->buildTagString(array_merge($this->tags, $tags)).':1|c';
     }
 
     /**
      * {@inheritdoc}
      */
-    public function decrement($variable)
+    public function decrement($variable, $tags = array())
     {
-        $this->data[] = $variable.$this->tags.':-1|c';
+        $this->data[] = $variable.$this->buildTagString(array_merge($this->tags, $tags)).':-1|c';
     }
 
     /**
      * {@inheritdoc}
      */
-    public function measure($variable, $value)
+    public function measure($variable, $value, $tags = array())
     {
-        $this->data[] = sprintf('%s%s:%s|c', $variable, $this->tags, $value);
+        $this->data[] = sprintf('%s%s:%s|c', $variable, $this->buildTagString(array_merge($this->tags, $tags)), $value);
     }
 
     /**
      * {@inheritdoc}
      */
-    public function gauge($variable, $value)
+    public function gauge($variable, $value, $tags = array())
     {
-        $this->data[] = sprintf('%s%s:%s|g', $variable, $this->tags, $value);
+        $this->data[] = sprintf('%s%s:%s|g', $variable, $this->buildTagString(array_merge($this->tags, $tags)), $value);
     }
 
     /**
      * @param $variable
      * @param $value
+     * @param array $tags
      */
-    public function set($variable, $value)
+    public function set($variable, $value, $tags = array())
     {
-        $this->data[] = sprintf('%s%s:%s|s', $variable, $this->tags, $value);
+        $this->data[] = sprintf('%s%s:%s|s', $variable, $this->buildTagString(array_merge($this->tags, $tags)), $value);
     }
 
     /**
@@ -130,4 +131,19 @@ public function flush()
 
         $this->data = array();
     }
+
+	/**
+     * Given a key/value map of metric tags, builds them into a
+     * telegraf statsd tag string and returns the string.
+     *
+     * @param $tags array
+     *
+     * @return string
+     */
+    private function buildTagString($tags)
+    {
+		$tagString = http_build_query($tags, '', ',');
+        $tagString = (strlen($tagString) > 0 ? ','.$tagString : $tagString);
+		return $tagString;
+    }
 }
diff --git a/src/Beberlei/Metrics/Collector/Zabbix.php b/src/Beberlei/Metrics/Collector/Zabbix.php
index 0380680..214e064 100644
--- a/src/Beberlei/Metrics/Collector/Zabbix.php
+++ b/src/Beberlei/Metrics/Collector/Zabbix.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Collector;
 
 use Net\Zabbix\Sender;
diff --git a/src/Beberlei/Metrics/Factory.php b/src/Beberlei/Metrics/Factory.php
index 47afdcb..940b44c 100644
--- a/src/Beberlei/Metrics/Factory.php
+++ b/src/Beberlei/Metrics/Factory.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics;
 
 use Net\Zabbix\Sender;
diff --git a/src/Beberlei/Metrics/MetricsException.php b/src/Beberlei/Metrics/MetricsException.php
index debb904..2100609 100644
--- a/src/Beberlei/Metrics/MetricsException.php
+++ b/src/Beberlei/Metrics/MetricsException.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics;
 
 class MetricsException extends \Exception
diff --git a/src/Beberlei/Metrics/Tests/Collector/InMemoryTest.php b/src/Beberlei/Metrics/Tests/Collector/InMemoryTest.php
new file mode 100644
index 0000000..ec8f760
--- /dev/null
+++ b/src/Beberlei/Metrics/Tests/Collector/InMemoryTest.php
@@ -0,0 +1,134 @@
+<?php
+/**
+ * Beberlei Metrics.
+ *
+ * LICENSE
+ *
+ * This source file is subject to the MIT license that is bundled
+ * with this package in the file LICENSE.txt.
+ * If you did not receive a copy of the license and are unable to
+ * obtain it through the world-wide-web, please send an email
+ * to kontakt@beberlei.de so I can send you a copy immediately.
+ */
+
+namespace Beberlei\Metrics\Tests\Collector;
+
+use Beberlei\Metrics\Collector\InMemory;
+
+class InMemoryTest extends \PHPUnit_Framework_TestCase
+{
+    const VARIABLE_A = 'variable_a';
+    const VARIABLE_B = 'variable_b';
+
+    /** @var InMemory */
+    private $collector;
+
+    public function setUp()
+    {
+        $this->collector = new InMemory();
+    }
+
+    public function testIncrement()
+    {
+        $this->collector->increment(self::VARIABLE_A);
+        $this->collector->increment(self::VARIABLE_A);
+
+        $this->collector->increment(self::VARIABLE_B);
+
+        $this->assertEquals(2, $this->collector->getMeasure(self::VARIABLE_A));
+        $this->assertEquals(1, $this->collector->getMeasure(self::VARIABLE_B));
+    }
+
+    public function testDecrement()
+    {
+        $this->collector->increment(self::VARIABLE_A);
+        $this->collector->increment(self::VARIABLE_A);
+        $this->collector->decrement(self::VARIABLE_A);
+
+        $this->collector->decrement(self::VARIABLE_B);
+        $this->collector->decrement(self::VARIABLE_B);
+
+        $this->assertEquals(1, $this->collector->getMeasure(self::VARIABLE_A));
+        $this->assertEquals(-2, $this->collector->getMeasure(self::VARIABLE_B));
+    }
+
+    public function testTiming()
+    {
+        $this->collector->timing(self::VARIABLE_A, 123);
+
+        $this->collector->timing(self::VARIABLE_B, 111);
+        $this->collector->timing(self::VARIABLE_B, 112);
+
+        $this->assertEquals(123, $this->collector->getTiming(self::VARIABLE_A));
+        $this->assertEquals(112, $this->collector->getTiming(self::VARIABLE_B));
+    }
+
+    public function testMeasure()
+    {
+        $this->collector->measure(self::VARIABLE_A, 2);
+        $this->collector->measure(self::VARIABLE_A, -5);
+
+        $this->collector->measure(self::VARIABLE_B, 123);
+        $this->collector->measure(self::VARIABLE_B, 0);
+
+        $this->assertEquals(-3, $this->collector->getMeasure(self::VARIABLE_A));
+        $this->assertEquals(123, $this->collector->getMeasure(self::VARIABLE_B));
+    }
+
+    public function testSettingGauge()
+    {
+        $this->collector->gauge(self::VARIABLE_A, 2);
+        $this->collector->gauge(self::VARIABLE_A, 5);
+
+        $this->collector->gauge(self::VARIABLE_B, 123);
+        $this->collector->gauge(self::VARIABLE_B, 0);
+
+        $this->assertEquals(5, $this->collector->getGauge(self::VARIABLE_A));
+        $this->assertEquals(0, $this->collector->getGauge(self::VARIABLE_B));
+    }
+
+    public function testIncrementingGauge()
+    {
+        $this->collector->gauge(self::VARIABLE_A, '10');
+        $this->collector->gauge(self::VARIABLE_A, '+2');
+        $this->collector->gauge(self::VARIABLE_A, '-3');
+
+        $this->assertEquals(9, $this->collector->getGauge(self::VARIABLE_A));
+    }
+
+    public function testSettingGaugeToNegativeValue()
+    {
+        $this->collector->gauge(self::VARIABLE_A, 1); //sets to 1
+        $this->collector->gauge(self::VARIABLE_A, 2); //sets to 2
+        $this->collector->gauge(self::VARIABLE_A, -5); //decreases by 5
+        $this->assertEquals(-3, $this->collector->getGauge(self::VARIABLE_A));
+
+        $this->collector->gauge(self::VARIABLE_A, 0);
+        $this->collector->gauge(self::VARIABLE_A, -5);
+        $this->assertEquals(-5, $this->collector->getGauge(self::VARIABLE_A));
+    }
+
+    public function testTypesOfMetricsAreSeparate()
+    {
+        $this->collector->increment(self::VARIABLE_A);
+        $this->collector->gauge(self::VARIABLE_A, 2);
+        $this->collector->timing(self::VARIABLE_A, 3);
+
+        $this->assertEquals(1, $this->collector->getMeasure(self::VARIABLE_A));
+        $this->assertEquals(2, $this->collector->getGauge(self::VARIABLE_A));
+        $this->assertEquals(3, $this->collector->getTiming(self::VARIABLE_A));
+    }
+
+    public function testFlushClearsData()
+    {
+        $this->collector->increment(self::VARIABLE_A);
+        $this->collector->gauge(self::VARIABLE_A, 2);
+        $this->collector->timing(self::VARIABLE_A, 3);
+
+        $this->collector->flush();
+
+        $this->assertEquals(0, $this->collector->getMeasure(self::VARIABLE_A));
+        $this->assertEquals(0, $this->collector->getGauge(self::VARIABLE_A));
+        $this->assertEquals(0, $this->collector->getTiming(self::VARIABLE_A));
+    }
+}
diff --git a/src/Beberlei/Metrics/Tests/Collector/InfluxDBTest.php b/src/Beberlei/Metrics/Tests/Collector/InfluxDBTest.php
old mode 100644
new mode 100755
index 70ec9d8..c9b78cb
--- a/src/Beberlei/Metrics/Tests/Collector/InfluxDBTest.php
+++ b/src/Beberlei/Metrics/Tests/Collector/InfluxDBTest.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Tests\Collector;
 
 use PHPUnit_Framework_MockObject_MockObject;
@@ -140,4 +141,54 @@ public function testCollectMeasureWithTags()
         $this->collector->measure('series-name', 47.11);
         $this->collector->flush();
     }
+
+	public function testCollectMeasureWithInlineTags()
+    {
+        $globalTags = array(
+            'dc' => 'west',
+            'node' => 'nemesis101',
+			);
+
+		$inlineTags = array(
+			'resource' => 'stuff'
+			);
+
+		$expectedTags = array_merge($globalTags, $inlineTags);
+
+        $expectedArgs = array(
+            'points' => array(
+                array(
+                    'measurement' => 'series-name',
+                    'fields' => array('value' => 47.11),
+					),
+				),
+            'tags' => $expectedTags,
+			);
+
+		$expectedArgs2 = array(
+            'points' => array(
+                array(
+                    'measurement' => 'series-name-2',
+                    'fields' => array('value' => 53.22),
+					),
+				),
+            'tags' => $globalTags,
+			);
+
+        $this->client->expects($this->exactly(2))
+            ->method('mark');
+
+        $this->client->expects($this->at(0))
+            ->method('mark')
+            ->with($expectedArgs);
+
+		$this->client->expects($this->at(1))
+            ->method('mark')
+            ->with($expectedArgs2);
+
+        $this->collector->setTags($globalTags);
+        $this->collector->measure('series-name', 47.11, $inlineTags);
+        $this->collector->measure('series-name-2', 53.22);
+        $this->collector->flush();
+    }
 }
diff --git a/src/Beberlei/Metrics/Tests/Collector/PrometheusTest.php b/src/Beberlei/Metrics/Tests/Collector/PrometheusTest.php
old mode 100644
new mode 100755
index 7d2aae4..4384a14
--- a/src/Beberlei/Metrics/Tests/Collector/PrometheusTest.php
+++ b/src/Beberlei/Metrics/Tests/Collector/PrometheusTest.php
@@ -10,6 +10,7 @@
  * obtain it through the world-wide-web, please send an email
  * to kontakt@beberlei.de so I can send you a copy immediately.
  */
+
 namespace Beberlei\Metrics\Tests\Collector;
 
 use Beberlei\Metrics\Collector\Prometheus;
@@ -96,6 +97,57 @@ public function testMeasureWithTags()
         $this->collector->flush();
     }
 
+	public function testMeasureWithInlineTags()
+    {
+        $expectedVariableValue = 123;
+        $expectedVariableValue2 = 456;
+        $globalTags = array(
+			'tag1' => 'value1',
+			'tag2' => 'value2',
+			);
+		$inlineTags = array(
+			'tag3' => 'value3',
+			);
+
+        $gaugeMock = $this->getMockBuilder('\\Prometheus\\Gauge')
+            ->disableOriginalConstructor()
+            ->getMock()
+			;
+        $gaugeMock2 = $this->getMockBuilder('\\Prometheus\\Gauge')
+            ->disableOriginalConstructor()
+            ->getMock()
+			;
+        $gaugeMock
+            ->expects($this->once())
+            ->method('set')
+            ->with($expectedVariableValue, array_values(array_merge($globalTags, $inlineTags)))
+			;
+        $gaugeMock2
+			->expects($this->once())
+            ->method('set')
+            ->with($expectedVariableValue2, array_values($globalTags))
+			;
+
+        $this->collectorRegistryMock
+            ->expects($this->at(0))
+            ->method('getGauge')
+            ->with(self::TEST_NAMESPACE, self::TEST_VARIABLE_NAME)
+            ->willReturn($gaugeMock)
+			;
+        $this->collectorRegistryMock
+            ->expects($this->at(1))
+            ->method('getGauge')
+            ->with(self::TEST_NAMESPACE, self::TEST_VARIABLE_NAME.'_2')
+            ->willReturn($gaugeMock2)
+			;
+
+        $this->collector->setTags($globalTags);
+
+        $this->collector->measure(self::TEST_VARIABLE_NAME, $expectedVariableValue, $inlineTags);
+        $this->collector->measure(self::TEST_VARIABLE_NAME.'_2', $expectedVariableValue2);
+        $this->collector->flush();
+    }
+
     public function testIncrement()
     {
         $gaugeMock = $this->getMockBuilder('\\Prometheus\\Gauge')
@@ -149,6 +201,55 @@ public function testIncrementWithTags()
         $this->collector->flush();
     }
 
+    public function testIncrementWithInlineTags()
+    {
+		$globalTags = array(
+            'tag1' => 'value1',
+            'tag2' => 'value2',
+			);
+		$inlineTags = array(
+			'tag3' => 'value3',
+			);
+
+        $gaugeMock = $this->getMockBuilder('\\Prometheus\\Gauge')
+            ->disableOriginalConstructor()
+            ->getMock()
+        ;
+        $gaugeMock2 = $this->getMockBuilder('\\Prometheus\\Gauge')
+            ->disableOriginalConstructor()
+            ->getMock()
+        ;
+        $gaugeMock
+            ->expects($this->once())
+            ->method('inc')
+            ->with(array_values(array_merge($globalTags, $inlineTags)))
+        ;
+        $gaugeMock2
+            ->expects($this->once())
+            ->method('inc')
+            ->with(array_values($globalTags))
+        ;
+
+        $this->collectorRegistryMock
+            ->expects($this->at(0))
+            ->method('getGauge')
+            ->with(self::TEST_NAMESPACE, self::TEST_VARIABLE_NAME)
+            ->willReturn($gaugeMock)
+        ;
+        $this->collectorRegistryMock
+            ->expects($this->at(1))
+            ->method('getGauge')
+            ->with(self::TEST_NAMESPACE, self::TEST_VARIABLE_NAME.'_2')
+            ->willReturn($gaugeMock2)
+        ;
+
+        $this->collector->setTags($globalTags);
+
+        $this->collector->increment(self::TEST_VARIABLE_NAME, $inlineTags);
+        $this->collector->increment(self::TEST_VARIABLE_NAME.'_2');
+        $this->collector->flush();
+    }
+
     public function testDecrement()
     {
         $gaugeMock = $this->getMockBuilder('\\Prometheus\\Gauge')
@@ -202,6 +303,55 @@ public function testDecrementWithTags()
         $this->collector->flush();
     }
 
+	public function testDecrementWithInlineTags()
+    {
+		$globalTags = array(
+            'tag1' => 'value1',
+            'tag2' => 'value2',
+			);
+		$inlineTags = array(
+			'tag3' => 'value3',
+			);
+
+        $gaugeMock = $this->getMockBuilder('\\Prometheus\\Gauge')
+            ->disableOriginalConstructor()
+            ->getMock()
+			;
+        $gaugeMock2 = $this->getMockBuilder('\\Prometheus\\Gauge')
+            ->disableOriginalConstructor()
+            ->getMock()
+			;
+        $gaugeMock
+            ->expects($this->once())
+            ->method('dec')
+            ->with(array_values(array_merge($globalTags, $inlineTags)))
+			;
+        $gaugeMock2
+            ->expects($this->once())
+            ->method('dec')
+            ->with(array_values($globalTags))
+			;
+
+        $this->collectorRegistryMock
+            ->expects($this->at(0))
+            ->method('getGauge')
+            ->with(self::TEST_NAMESPACE, self::TEST_VARIABLE_NAME)
+            ->willReturn($gaugeMock)
+			;
+        $this->collectorRegistryMock
+            ->expects($this->at(1))
+            ->method('getGauge')
+            ->with(self::TEST_NAMESPACE, self::TEST_VARIABLE_NAME.'_2')
+            ->willReturn($gaugeMock2)
+			;
+
+        $this->collector->setTags($globalTags);
+
+        $this->collector->decrement(self::TEST_VARIABLE_NAME, $inlineTags);
+        $this->collector->decrement(self::TEST_VARIABLE_NAME.'_2');
+        $this->collector->flush();
+    }
+
     public function testTiming()
     {
         $expectedVariableValue = 123;
@@ -258,6 +408,57 @@ public function testTimingWithTags()
         $this->collector->flush();
     }
 
+    public function testTimingWithInlineTags()
+    {
+        $expectedVariableValue = 123;
+		$expectedVariableValue2 = 456;
+        $globalTags = array(
+			'tag1' => 'value1',
+			'tag2' => 'value2',
+			);
+		$inlineTags = array(
+			'tag3' => 'value3',
+			);
+
+        $gaugeMock = $this->getMockBuilder('\\Prometheus\\Gauge')
+            ->disableOriginalConstructor()
+            ->getMock()
+        ;
+        $gaugeMock2 = $this->getMockBuilder('\\Prometheus\\Gauge')
+            ->disableOriginalConstructor()
+            ->getMock()
+        ;
+        $gaugeMock
+            ->expects($this->once())
+            ->method('set')
+            ->with($expectedVariableValue, array_values(array_merge($globalTags, $inlineTags)))
+        ;
+        $gaugeMock2
+            ->expects($this->once())
+            ->method('set')
+            ->with($expectedVariableValue, array_values($globalTags))
+        ;
+
+        $this->collectorRegistryMock
+            ->expects($this->at(0))
+            ->method('getGauge')
+            ->with(self::TEST_NAMESPACE, self::TEST_VARIABLE_NAME)
+            ->willReturn($gaugeMock)
+        ;
+        $this->collectorRegistryMock
+            ->expects($this->at(1))
+            ->method('getGauge')
+            ->with(self::TEST_NAMESPACE, self::TEST_VARIABLE_NAME.'_2')
+            ->willReturn($gaugeMock2)
+        ;
+
+        $this->collector->setTags($globalTags);
+
+        $this->collector->timing(self::TEST_VARIABLE_NAME, $expectedVariableValue, $inlineTags);
+        $this->collector->timing(self::TEST_VARIABLE_NAME.'_2', $expectedVariableValue);
+        $this->collector->flush();
+    }
+
     public function testMeasureWhenSetNewVariableWithTags()
     {
         $expectedVariableValue = 123;