diff --git a/composer.json b/composer.json
index e84bd3c..f144772 100644
--- a/composer.json
+++ b/composer.json
@@ -18,7 +18,7 @@
         "processing"
     ],
     "require": {
-        "php": ">=5.6",
+        "php": ">=5.4",
         "predis/predis": "^1.0"
     },
     "require-dev": {
diff --git a/examples/basic.php b/examples/basic.php
index cc7b7e4..2eda0b7 100644
--- a/examples/basic.php
+++ b/examples/basic.php
@@ -1,5 +1,8 @@
 <?php
 include __DIR__.'/../vendor/autoload.php';
+function _print($id, $retry){
+    var_dump(sprintf('Pushed job with id %s and retry:%d', $id, $retry));
+}
 
 // connect to database 0 on 127.0.0.1
 $redis = new Predis\Client('tcp://127.0.0.1:6379/0');
@@ -14,6 +17,8 @@
     70
 ];
 
-$id = $client->push('ProcessImage', $args);
+$id = $client->push('ProcessImage', $args, true);
+_print($id, true);
 
-var_dump(sprintf('Pushed job with id %s', $id));
\ No newline at end of file
+$id = $client->push('ProcessImage', $args, false);
+_print($id, false);
diff --git a/examples/bulk.php b/examples/bulk.php
index f9258f0..9926044 100644
--- a/examples/bulk.php
+++ b/examples/bulk.php
@@ -11,7 +11,7 @@
 $jobs = [
     ['class' => 'ProcessImage', 'args' => [['url' => 'http://i.imgur.com/hlAsa4k.jpg'], true, 12]],
     ['class' => 'ProcessImage', 'args' => [['url' => 'http://i.imgur.com/hlAsa4k.jpg'], true, null]],
-    ['class' => 'ProcessImage', 'args' => [['url' => 'http://i.imgur.com/hlAsa4k.jpg'], false, 45]]
+    ['class' => 'ProcessImage', 'args' => [['url' => 'http://i.imgur.com/hlAsa4k.jpg']], 'at' => microtime(true)+60*6, 'retry' => false]
 ];
 
 // push jobs to a different queue
diff --git a/lib/Client.php b/lib/Client.php
index 0493707..f0ff0cc 100644
--- a/lib/Client.php
+++ b/lib/Client.php
@@ -45,12 +45,13 @@ public function __construct(\Predis\Client $redis, $namespace = null, $serialize
      * @param string $class
      * @param array  $args
      * @param string $queue
+     * @param bool   $retry
      * @return string
      */
-    public function push($class, $args = [], $queue = self::QUEUE)
+    public function push($class, $args = [], $retry = true, $queue = self::QUEUE)
     {
         $jobId = $this->idGenerator->generate();
-        $this->atomicPush($jobId, $class, $args, $queue);
+        $this->atomicPush($jobId, $class, $args, $queue, $retry);
 
         return $jobId;
     }
@@ -62,12 +63,13 @@ public function push($class, $args = [], $queue = self::QUEUE)
      * @param string $class
      * @param array  $args
      * @param string $queue
+     * @param bool   $retry
      * @return string
      */
-    public function schedule($doAt, $class, $args = [], $queue = self::QUEUE)
+    public function schedule($doAt, $class, $args = [], $retry = true, $queue = self::QUEUE)
     {
         $jobId = $this->idGenerator->generate();
-        $this->atomicPush($jobId, $class, $args, $queue, $doAt);
+        $this->atomicPush($jobId, $class, $args, $queue, $retry, $doAt);
 
         return $jobId;
     }
@@ -79,7 +81,9 @@ public function schedule($doAt, $class, $args = [], $queue = self::QUEUE)
      * $jobs = [
      *  [
      *      'class' => 'SomeClass',
-     *      'args' => array()
+     *      'args' => array(),
+     *      'retry' => false,
+     *      'at' => microtime(true)
      *  ]
      * ];
      *
@@ -99,9 +103,12 @@ public function pushBulk($jobs = [], $queue = self::QUEUE)
                 throw new Exception('pushBulk: each job needs args');
             }
 
+            $retry = isset($job['retry']) ? $job['retry'] : true;
+            $doAt = isset($job['at']) ? $job['at'] : null;
+
             $jobId = $this->idGenerator->generate();
             array_push($ids, $jobId);
-            $this->atomicPush($jobId, $job['class'], $job['args'], $queue);
+            $this->atomicPush($jobId, $job['class'], $job['args'], $queue, $retry, $doAt);
         }
 
         return $ids;
@@ -114,10 +121,11 @@ public function pushBulk($jobs = [], $queue = self::QUEUE)
      * @param string     $class
      * @param array      $args
      * @param string     $queue
+     * @param bool       $retry
      * @param float|null $doAt
      * @throws exception Exception
      */
-    private function atomicPush($jobId, $class, $args = [], $queue = self::QUEUE, $doAt = null)
+    private function atomicPush($jobId, $class, $args = [], $queue = self::QUEUE, $retry = true, $doAt = null)
     {
         if (array_values($args) !== $args) {
             throw new Exception('Associative arrays in job args are not allowed');
@@ -127,7 +135,7 @@ private function atomicPush($jobId, $class, $args = [], $queue = self::QUEUE, $d
             throw new Exception('at argument needs to be in a unix epoch format. Use microtime(true).');
         }
 
-        $job = $this->serializer->serialize($jobId, $class, $args);
+        $job = $this->serializer->serialize($jobId, $class, $args, $retry);
 
         if ($doAt === null) {
             $this->redis->sadd($this->name('queues'), $queue);
@@ -141,7 +149,7 @@ private function atomicPush($jobId, $class, $args = [], $queue = self::QUEUE, $d
      * @param string ...$key
      * @return string
      */
-    private function name(...$key)
+    private function name()
     {
         return implode(':', array_filter(array_merge([$this->namespace], func_get_args()), 'strlen'));
     }
diff --git a/lib/Serializer.php b/lib/Serializer.php
index 4029439..45aaec4 100644
--- a/lib/Serializer.php
+++ b/lib/Serializer.php
@@ -17,20 +17,14 @@ class Serializer
      * @return string
      * @throws exception Exception
      */
-    public function serialize($jobId, $class, $args = [])
+    public function serialize($jobId, $class, $args = [], $retry = true)
     {
         $class = is_object($class) ? get_class($class) : $class;
-        $retry = (isset($args['retry']) && is_bool($args['retry'])) ? $args['retry'] : true;
-        $createdAt = isset($args['created_at']) ? $args['created_at'] : microtime(true);
-
-        if (!is_float($createdAt) && is_string($createdAt)) {
-            throw new Exception('created_at argument needs to be in a unix epoch format. Use microtime(true).');
-        }
 
         $data = [
             'class' => $class,
             'jid' => $jobId,
-            'created_at' => $createdAt,
+            'created_at' => microtime(true),
             'enqueued_at' => microtime(true),
             'args' => $args,
             'retry' => $retry,