diff --git a/lib/UvReactor.php b/lib/UvReactor.php
index 314fa6d..1aa0575 100644
--- a/lib/UvReactor.php
+++ b/lib/UvReactor.php
@@ -14,11 +14,13 @@ class UvReactor implements SignalReactor {
     private $stopException;
     private $resolution = 1000;
     private $isWindows;
+    private $immediates = [];
 
     private static $MODE_ONCE = 0;
     private static $MODE_REPEAT = 1;
     private static $MODE_STREAM = 2;
     private static $MODE_SIGNAL = 3;
+    private static $MODE_IMMEDIATE = 4;
 
     public function __construct($newLoop = false) {
         $this->loop = $newLoop ? uv_loop_new() : uv_default_loop();
@@ -48,8 +50,13 @@ class UvReactor implements SignalReactor {
         if ($onStart) {
             $this->immediately(function() use ($onStart) { $onStart($this); });
         }
-        uv_run($this->loop);
-        $this->isRunning = false;
+
+        while ($this->isRunning) {
+            if ($this->immediates && !$this->doImmediates()) {
+                break;
+            }
+            uv_run($this->loop, \UV::RUN_NOWAIT | \UV::RUN_ONCE);
+        }
 
         if ($this->stopException) {
             $e = $this->stopException;
@@ -58,6 +65,23 @@ class UvReactor implements SignalReactor {
         }
     }
 
+    private function doImmediates() {
+        $immediates = $this->immediates;
+        foreach ($immediates as $watcherId => $callback) {
+            $callback($this);
+            unset(
+                $this->immediates[$watcherId],
+                $this->watchers[$watcherId]
+            );
+            if (!$this->isRunning) {
+                // If a watcher stops the reactor break out of the loop
+                break;
+            }
+        }
+
+        return $this->isRunning;
+    }
+
     /**
      * Execute a single event loop iteration
      *
@@ -65,8 +89,16 @@ class UvReactor implements SignalReactor {
      * @return void
      */
     public function tick() {
+        if ($this->isRunning) {
+            return;
+        }
+
         $this->isRunning = true;
-        uv_run_once($this->loop);
+
+        if (empty($this->immediates) || $this->doImmediates()) {
+            uv_run($this->loop, \UV::RUN_NOWAIT | \UV::RUN_ONCE);
+        }
+
         $this->isRunning = false;
 
         if ($this->stopException) {
@@ -83,6 +115,7 @@ class UvReactor implements SignalReactor {
      */
     public function stop() {
         uv_stop($this->loop);
+        $this->isRunning = false;
     }
 
     /**
@@ -92,7 +125,18 @@ class UvReactor implements SignalReactor {
      * @return int Returns a unique integer watcher ID
      */
     public function immediately(callable $callback) {
-        return $this->startTimer($callback, $msDelay = 0, $msInterval = 0, self::$MODE_ONCE);
+        $watcherId = $this->lastWatcherId++;
+        $this->immediates[$watcherId] = $callback;
+
+        $watcher = new \StdClass;
+        $watcher->id = $watcherId;
+        $watcher->mode = self::$MODE_IMMEDIATE;
+        $watcher->callback = $callback;
+        $watcher->isEnabled = true;
+
+        $this->watchers[$watcher->id] = $watcher;
+
+        return $watcherId;
     }
 
     /**
@@ -327,6 +371,9 @@ class UvReactor implements SignalReactor {
                 case self::$MODE_SIGNAL:
                     uv_signal_stop($watcher->uvStruct);
                     break;
+                case self::$MODE_IMMEDIATE:
+                    unset($this->immediates[$watcherId]);
+                    break;
                 default:
                     uv_timer_stop($watcher->uvStruct);
                     break;
@@ -365,6 +412,9 @@ class UvReactor implements SignalReactor {
             case self::$MODE_SIGNAL:
                 uv_signal_stop($watcher->uvStruct);
                 break;
+            case self::$MODE_IMMEDIATE:
+                unset($this->immediates[$watcher->id]);
+                break;
             default:
                 uv_timer_stop($watcher->uvStruct);
                 break;
@@ -397,6 +447,9 @@ class UvReactor implements SignalReactor {
             case self::$MODE_SIGNAL:
                 uv_signal_start($watcher->uvStruct, $watcher->callback, $watcher->signo);
                 break;
+            case self::$MODE_IMMEDIATE:
+                $this->immediates[$watcher->id] = $watcher->callback;
+                break;
             default:
                 uv_timer_start($watcher->uvStruct, $watcher->msDelay, $watcher->msInterval, $watcher->callback);
                 break;