diff --git a/includes/application/code/community/Legacies.php b/includes/application/code/community/Legacies.php
index 473b39f..87a36f4 100644
--- a/includes/application/code/community/Legacies.php
+++ b/includes/application/code/community/Legacies.php
@@ -9,6 +9,8 @@ class Legacies
     public static $request = null;
     public static $response = null;
 
+    protected static $_now = null;
+
     public static function registerListener($event, $listener)
     {
         if (!isset(self::$_listeners[$event])) {
@@ -72,4 +74,12 @@ class Legacies
     {
         return 'fr_FR';
     }
+
+    public static function now()
+    {
+        if (self::$_now === null) {
+            self::$_now = time();
+        }
+        return self::$_now;
+    }
 }
\ No newline at end of file
diff --git a/includes/application/code/community/Legacies/Empire/Model/BuilderAbstract.php b/includes/application/code/community/Legacies/Empire/Model/BuilderAbstract.php
index 4f1214c..00262a9 100644
--- a/includes/application/code/community/Legacies/Empire/Model/BuilderAbstract.php
+++ b/includes/application/code/community/Legacies/Empire/Model/BuilderAbstract.php
@@ -42,8 +42,12 @@ abstract class Legacies_Empire_Model_BuilderAbstract
     {
         $this->_currentPlanet = $currentPlanet;
         $this->_currentUser = $currentUser;
+
+        $this->init();
     }
 
+    abstract public function init();
+
     abstract protected function _initItem();
 
     public function enqueue()
@@ -51,14 +55,14 @@ abstract class Legacies_Empire_Model_BuilderAbstract
         $params = func_get_args();
         $item = call_user_func_array(array($this, '_initItem'), $params);
         $item->setIndex($this->_index);
-        $queue[$this->_index++] = $item;
+        $this->_queue[$this->_index++] = $item;
 
         return $this;
     }
 
     public function dequeue($itemIndex)
     {
-        unset($itemIndex);
+        unset($this->_queue[$itemIndex]);
 
         return $this;
     }
@@ -84,12 +88,17 @@ abstract class Legacies_Empire_Model_BuilderAbstract
     protected function _unserializeQueue($serialized)
     {
         $this->clearQueue();
-        $reflection = new ReflectionClass($this->_itemClass);
 
         $unserialized = unserialize($serialized);
-        foreach ($unserialized as $itemData) {
-            $this->_enqueue($reflection->newInstance($itemData));
+        if ($unserialized === false) {
+            $this->_queue = array();
+            return $this;
         }
+
+        foreach ($unserialized as $itemData) {
+            call_user_func_array(array($this, 'enqueue'), $itemData);
+        }
+
         return $this;
     }
 
@@ -103,9 +112,6 @@ abstract class Legacies_Empire_Model_BuilderAbstract
         return $this->_queue;
     }
 
-    abstract public function enqueue($item);
-    abstract public function dequeue($item);
-
     public function clearQueue()
     {
         $this->_queue = array();
@@ -158,4 +164,48 @@ abstract class Legacies_Empire_Model_BuilderAbstract
 
     abstract public function getResourcesNeeded($typeId, $level);
     abstract public function getBuildingTime($typeId, $level);
+
+    public function serialize()
+    {
+        return $this->_serializeQueue();
+    }
+
+    public function unserialize($serialized)
+    {
+        $this->_unserializeQueue($serialized);
+    }
+
+    public function count()
+    {
+        return count($this->_queue);
+    }
+
+    public function current()
+    {
+        return current($this->_queue);
+    }
+
+    public function next()
+    {
+        $element = next($this->_queue);
+        $this->_index = key($this->_queue);
+
+        return $element;
+    }
+
+    public function key()
+    {
+        return $this->_index;
+    }
+
+    public function valid()
+    {
+        return $this->current() !== false;
+    }
+
+    public function rewind()
+    {
+        reset($this->_queue);
+        $this->_index = 0;
+    }
 }
\ No newline at end of file
diff --git a/includes/application/code/community/Legacies/Empire/Model/Planet.php b/includes/application/code/community/Legacies/Empire/Model/Planet.php
index bb59b8a..aa9ea68 100644
--- a/includes/application/code/community/Legacies/Empire/Model/Planet.php
+++ b/includes/application/code/community/Legacies/Empire/Model/Planet.php
@@ -15,7 +15,9 @@ class Legacies_Empire_Model_Planet
 
     protected $_user = null;
     protected $_moon = null;
-    protected $_now = null;
+
+    protected $_builder = null;
+    protected $_shipyard = null;
 
     protected static $_instances = array();
 
@@ -48,17 +50,19 @@ class Legacies_Empire_Model_Planet
 
     public function _init()
     {
-        $this->_now = time();
         $this->_tableName = 'planets';
         $this->_idFieldName = 'id';
+
+        $this->_builder = new Legacies_Empire_Model_Planet_Builder($this, $this->getUser());
     }
 
-    /**
-     * @deprecated
-     */
-    protected function _now()
+    public function _afterLoad()
     {
-        return $this->_now;
+        parent::_afterLoad();
+
+        $this->_builder->init();
+
+        return $this;
     }
 
     public function getLastUpdate()
@@ -73,22 +77,20 @@ class Legacies_Empire_Model_Planet
 
     public function updateStorages($time = null)
     {
-        Math::setPrecision(10);
+        Math::setPrecision(50);
         $resources = Legacies_Empire_Model_Game_Resources::getSingleton();
         foreach ($resources->getAllDatas() as $resource => $resourceData) {
             if (!isset($resourceData['storage_field']) || $resourceData['storage_field'] === null && $this['rpg_stockeur'] === null) {
                 continue;
             }
 
-            Math::setPrecision(1);
-            $officerEnhancement = Math::add(Math::mul(.5, $this->getData('rpg_stockeur'), 50), 1, 10, 50);
+            $officerEnhancement = (.5 * $this->getData('rpg_stockeur')) + 1;
 
-            Math::setPrecision(0);
-            $storageEnhancementFactor = Math::pow(1.6, $this[Legacies_Empire::getFieldName($resourceData['storage'])]);
+            $storageEnhancementFactor = Math::floor(Math::pow(1.6, $this[Legacies_Empire::getFieldName($resourceData['storage'])]));
             $storageEnhancement = Math::mul(BASE_STORAGE_SIZE / 2, $storageEnhancementFactor);
 
             $value = Math::mul(MAX_OVERFLOW, Math::mul($officerEnhancement, Math::add(BASE_STORAGE_SIZE, $storageEnhancement)));
-            $this->setData($resourceData['storage_field'], $value);
+            $this->setData($resourceData['storage_field'], Math::floor($value));
         }
         Math::setPrecision();
 
@@ -102,7 +104,7 @@ class Legacies_Empire_Model_Planet
         $production = Legacies_Empire_Model_Game_Production::getSingleton();
 
         if ($time === null) {
-            $time = $this->_now();
+            $time = Legacies::now();
         }
 
         if (!$this->isPlanet()) {
@@ -207,11 +209,10 @@ class Legacies_Empire_Model_Planet
         $resources = Legacies_Empire_Model_Game_Resources::getSingleton();
 
         if ($time === null) {
-            $time = $this->_now();
+            $time = Legacies::now();
         }
 
         $timeDiff = ($time - $this->getLastUpdate()) / 3600;
-        var_dump($time, $this->getLastUpdate(), $timeDiff);
         foreach ($resources->getAllDatas() as $resourceId => $resourceConfig) {
             $production = Math::mul($this->getData($resourceConfig['production_field']), $timeDiff);
             $this->setData($resourceConfig['field'], Math::min($production, $this->getData($resourceConfig['storage_field'])));
@@ -244,6 +245,28 @@ class Legacies_Empire_Model_Planet
         return $this->_user;
     }
 
+    public function setUser(Legacies_Empire_Model_User $user)
+    {
+        $this->_user = $user;
+
+        return $this;
+    }
+
+    public function getShipyard()
+    {
+        if ($this->_shipyard === null) {
+            $this->_shipyard = new Legacies_Empire_Model_Planet_Building_Shipyard($this, $this->getUser());
+        }
+        return $this->_shipyard;
+    }
+
+    public function setShipyard(Legacies_Empire_Model_Planet_Building_Shipyard $shipyard)
+    {
+        $this->_shipyard = $shipyard;
+
+        return $this;
+    }
+
     public function isPlanet()
     {
         return (bool) ($this->getData('planet_type') == self::TYPE_PLANET);
@@ -357,38 +380,44 @@ class Legacies_Empire_Model_Planet
         return $this->hasData($fields[$elementId]) && Math::comp($this->getElement($elementId), $levelRequired) > 0;
     }
 
-    public function appendQueue($buildingId)
+    public function appendQueue($buildingId, $time = null, $destroy = false)
     {
         $types = Legacies_Empire_Model_Game_Types::getSingleton();
+        $prices = Legacies_Empire_Model_Game_Prices::getSingleton();
 
         if (!$types->is($buildingId, Legacies_Empire::TYPE_BUILDING)) {
             return $this;
         }
 
-        if (!$this->checkAvailability($buildingId)) {
+        if ($destroy === false && !$this->checkAvailability($buildingId)) {
             return $this;
         }
 
-        // Dispatch event
+        // Dispatch 'planet.building.append-queue.before' event
         Legacies::dispatchEvent('planet.building.append-queue.before', array(
-            'ship_id'  => $shipId,
-            'qty'      => $qty,
-            'shipyard' => $this,
-            'planet'   => $this->_currentPlanet,
-            'user'     => $this->_currentUser
+            'bulding_id' => $buildingId,
+            'level'      => $this->getElement($buildingId),
+            'planet'     => $this,
+            'user'       => $this->getUser(),
+            'destroy'    => $destroy
             ));
 
+        $this->_builder->enqueue($buildingId, $level, $time);
+
+        //$elementBasePrice = $prices;
+        /*
         foreach ($this->_resourcesTypes as $resourceType) {
             $this->setData($resourceType, Math::sub($this->getData($resourceType), $resourcesNeeded[$resourceType]));
         }
+        */
 
-        // Dispatch event
+        // Dispatch 'planet.shipyard.append-queue.after' event
         Legacies::dispatchEvent('planet.shipyard.append-queue.after', array(
-            'ship_id'  => $shipId,
-            'qty'      => $qty,
-            'shipyard' => $this,
-            'planet'   => $this->_currentPlanet,
-            'user'     => $this->_currentUser
+            'bulding_id' => $buildingId,
+            'level'      => $this->getElement($buildingId),
+            'planet'     => $this,
+            'user'       => $this->getUser(),
+            'destroy'    => $destroy
             ));
 
         return $this;
@@ -551,6 +580,7 @@ class Legacies_Empire_Model_Planet
             }
 
             $user = $planet->getUser();
+            /*
             if (($queue = $planet->getData('b_building_id')) != '0') { //FIXME: refactor buildings construciton list
                 $explodedQueue = explode(';', $queue);
                 foreach ($explodedQueue as $item) {
@@ -558,9 +588,9 @@ class Legacies_Empire_Model_Planet
 
                     if ($partialTime < $time) {
                         $planet->updateResources($partialTime);
-                        /*if (CheckPlanetBuildingQueue($planet, $user)) {
+                        if (CheckPlanetBuildingQueue($planet, $user)) {
                             SetNextQueueElementOnTop($planet, $user);
-                        }*/
+                        }
                     } else {
                         $planet->updateResources($time);
                         break;
@@ -568,7 +598,9 @@ class Legacies_Empire_Model_Planet
                 }
             } else {
                 $planet->updateResources($time);
-            }
+            }*/
+            $planet->updateResources($time);
+            $planet->getShipyard()->updateQueue($time);
             $planet->setLastUpdate($time);
         }
     }
diff --git a/includes/application/code/community/Legacies/Empire/Model/Planet/Builder.php b/includes/application/code/community/Legacies/Empire/Model/Planet/Builder.php
new file mode 100644
index 0000000..4da968b
--- /dev/null
+++ b/includes/application/code/community/Legacies/Empire/Model/Planet/Builder.php
@@ -0,0 +1,39 @@
+<?php
+
+class Legacies_Empire_Model_Planet_Builder
+    extends Legacies_Empire_Model_BuilderAbstract
+{
+    public function init()
+    {
+        $this->_unserializeQueue($this->_currentPlanet->getData('b_building_id'));
+    }
+
+    /**
+     * @param int $buildingId
+     * @param int $level
+     * @param int $time
+     */
+    public function _initItem()
+    {
+        $buildingId = func_get_arg(0);
+        $level = func_get_arg(1);
+        $time = func_get_arg(2);
+
+        return new Legacies_Empire_Model_Planet_Building_Shipyard_Item(array(
+            'building_id' => $buildingId,
+            'level'       => $level,
+            'created_at'  => $time,
+            'updated_at'  => $time
+            ));
+    }
+
+    public function getResourcesNeeded($typeId, $level)
+    {
+        return array();
+    }
+
+    public function getBuildingTime($typeId, $level)
+    {
+        return 0;
+    }
+}
\ No newline at end of file
diff --git a/includes/application/code/community/Legacies/Empire/Model/Planet/Building/Shipyard.php b/includes/application/code/community/Legacies/Empire/Model/Planet/Building/Shipyard.php
index 9438f0f..f1afa51 100644
--- a/includes/application/code/community/Legacies/Empire/Model/Planet/Building/Shipyard.php
+++ b/includes/application/code/community/Legacies/Empire/Model/Planet/Building/Shipyard.php
@@ -56,15 +56,7 @@ class Legacies_Empire_Model_Planet_Building_Shipyard
      * construction queue
      * @var array
      */
-    protected $_queue = null;
-
-    /**
-     * Current timestamp
-     *
-     * @var int
-     * @deprecated
-     */
-    private $_now = 0;
+    protected $_builder = null;
 
     /**
      * Resource list
@@ -117,9 +109,7 @@ class Legacies_Empire_Model_Planet_Building_Shipyard
         $this->_currentPlanet = $currentPlanet;
         $this->_currentUser = $currentUser;
 
-        $this->_queue = new Legacies_Empire_Model_Planet_Building_Shipyard_Builder($currentPlanet, $currentUser);
-
-        $this->_now = time();
+        $this->_builder = new Legacies_Empire_Model_Planet_Building_Shipyard_Builder($currentPlanet, $currentUser);
     }
 
     /**
@@ -130,7 +120,7 @@ class Legacies_Empire_Model_Planet_Building_Shipyard
      */
     protected function _now()
     {
-        return $this->_now;
+        return Legacies::now();
     }
 
     /**
@@ -154,7 +144,7 @@ class Legacies_Empire_Model_Planet_Building_Shipyard
     {
         $types = Legacies_Empire_Model_Game_Types::getSingleton();
 
-        if (Math::comp($qty, 0) <= 0) {
+        if (Math::isPositive($qty)) {
             return $this;
         }
 
@@ -181,10 +171,10 @@ class Legacies_Empire_Model_Planet_Building_Shipyard
             'user'     => $this->_currentUser
             ));
 
-        $resourcesNeeded = $this->_getResourcesNeeded($shipId, $qty);
+        $resourcesNeeded = $this->getResourcesNeeded($shipId, $qty);
         $buildTime = $this->getBuildTime($shipId, $qty);
 
-        $this->_queue->enqueue($shipId, $qty);
+        $this->_queue->enqueue($shipId, $qty, now());
 
         foreach ($this->_resourcesTypes as $resourceType) {
             $this->_currentPlanet[$resourceType] = Math::sub($this->_currentPlanet[$resourceType], $resourcesNeeded[$resourceType]);
@@ -209,48 +199,7 @@ class Legacies_Empire_Model_Planet_Building_Shipyard
      */
     public function updateQueue($time = null)
     {
-        $fields = Legacies_Empire_Model_Game_FieldsAlias::getSingleton();
-
-        if ($time === null) {
-            $time = $this->_now();
-        }
-        $elapsedTime = $time - $this->_currentPlanet['b_hangar'];
-
-        // Dispatch event
-        Legacies::dispatchEvent('planet.shipyard.update-queue.before', array(
-            'shipyard' => $this,
-            'planet'   => $this->_currentPlanet,
-            'user'     => $this->_currentUser
-            ));
-
-        foreach ($this->_queue as $id => &$element) {
-            $shipId = $element->getData('ship_id');
-            $qty = $element->getData('qty');
-            $buildTime = $this->getBuildTime($shipId, $qty);
-
-            if ($elapsedTime >= $buildTime) {
-                $this->_currentPlanet[$fields[$shipId]] = Math::add($this->_currentPlanet[$fields[$shipId]], $qty);
-                $elapsedTime -= $buildTime;
-                unset($this->_queue[$id]);
-                continue;
-            }
-
-            $timeRatio = $elapsedTime / $buildTime;
-            $itemsBuilt = Math::mul($timeRatio, $qty);
-
-            $element->setData('updated_at', $time);
-            $element->setData('qty', Math::sub($qty, $itemsBuilt));
-            $this->_currentPlanet->setData($fields[$shipId], Math::add($this->_currentPlanet->getData($fields[$shipId]), $itemsBuilt));
-            break;
-        }
-        unset($element);
-
-        // Dispatch event
-        Legacies::dispatchEvent('planet.shipyard.update-queue.after', array(
-            'shipyard' => $this,
-            'planet'   => $this->_currentPlanet,
-            'user'     => $this->_currentUser
-            ));
+        $this->_builder->updateQueue($time);
 
         return $this;
     }
@@ -275,39 +224,7 @@ class Legacies_Empire_Model_Planet_Building_Shipyard
      */
     public function checkAvailability($shipId)
     {
-        $types = Legacies_Empire_Model_Game_Types::getSingleton();
-        $requirements = Legacies_Empire_Model_Game_Requirements::getSingleton();
-
-        if (!isset($requirements[$shipId]) || empty($requirements[$shipId])) {
-            return true;
-        }
-
-        foreach ($requirements[$shipId] as $requirement => $level) {
-            if ($types->is($requirement, Legacies_Empire::TYPE_BUILDING) && $this->_currentPlanet->hasElement($requirement, $level)) {
-                continue;
-            } else if ($types->is($requirement, Legacies_Empire::TYPE_RESEARCH) && $this->_currentUser->hasElement($requirement, $level)) {
-                continue;
-            } else if ($types->is($requirement, Legacies_Empire::TYPE_DEFENSE) && $this->_currentPlanet->hasElement($requirement, $level)) {
-                continue;
-            } else if ($types->is($requirement, Legacies_Empire::TYPE_SHIP) && $this->_currentPlanet->hasElement($requirement, $level)) {
-                continue;
-            }
-            return false;
-        }
-
-        try {
-            // Dispatch event. Throw an exception to break the avaliability.
-            Legacies::dispatchEvent('planet.shipyard.check-availability', array(
-                'ship_id'  => $shipId,
-                'shipyard' => $this,
-                'planet'   => $this->_currentPlanet,
-                'user'     => $this->_currentUser
-                ));
-        } catch (Exception $e) {
-            return false;
-        }
-
-        return true;
+        return $this->_builder->checkAvailability($shipId);
     }
 
     /**
@@ -320,13 +237,7 @@ class Legacies_Empire_Model_Planet_Building_Shipyard
      */
     protected function _checkMaximumQuantity($shipId, $qty)
     {
-        $max = $this->getMaximumBuildableElementsCount($shipId);
-
-        if (Math::comp($qty, $max) > 0) {
-            return $max;
-        }
-
-        return $qty;
+        return Math::min($qty, $this->getMaximumBuildableElementsCount($shipId));
     }
 
     /**
@@ -338,122 +249,17 @@ class Legacies_Empire_Model_Planet_Building_Shipyard
      */
     public function getMaximumBuildableElementsCount($shipId)
     {
-        $prices = Legacies_Empire_Model_Game_Prices::getSingleton();
-        $fields = Legacies_Empire_Model_Game_FieldsAlias::getSingleton();
-
-        $resources = array(
-            Legacies_Empire::RESOURCE_METAL,
-            Legacies_Empire::RESOURCE_CRISTAL,
-            Legacies_Empire::RESOURCE_DEUTERIUM,
-            Legacies_Empire::RESOURCE_ENERGY
-            );
-
-        $qty = 0;
-        foreach ($resources as $resourceId) {
-            if (isset($prices[$shipId]) && isset($prices[$shipId][$resourceId]) && Math::comp($prices[$shipId][$resourceId], 0) > 0) {
-                $maxQty = Math::floor(Math::div($this->_currentPlanet->getData($resourceId), $prices[$shipId][$resourceId]));
-
-                if ($maxQty == 0) {
-                    return 0;
-                }
-
-                if ($qty == 0 || Math::comp($maxQty, $qty) < 0) {
-                    $qty = $maxQty;
-                }
-            }
-        }
-
-        if ($qty == 0) {
-            return 0;
-        }
-
-        $limitedElementsQty = array(
-            Legacies_Empire::ID_DEFENSE_SMALL_SHIELD_DOME      => array(
-                'current'   => $this->_currentPlanet[$fields[Legacies_Empire::ID_DEFENSE_SMALL_SHIELD_DOME]],
-                'requested' => $this->_currentPlanet[$fields[Legacies_Empire::ID_DEFENSE_SMALL_SHIELD_DOME]],
-                'limit'     => 1
-                ),
-            Legacies_Empire::ID_DEFENSE_LARGE_SHIELD_DOME      => array(
-                'current'   => $this->_currentPlanet[$fields[Legacies_Empire::ID_DEFENSE_LARGE_SHIELD_DOME]],
-                'requested' => $this->_currentPlanet[$fields[Legacies_Empire::ID_DEFENSE_LARGE_SHIELD_DOME]],
-                'limit'     => 1
-                ),
-            Legacies_Empire::ID_SPECIAL_ANTIBALLISTIC_MISSILE  => array(
-                'current'   => $this->_currentPlanet[$fields[Legacies_Empire::ID_SPECIAL_ANTIBALLISTIC_MISSILE]],
-                'requested' => $this->_currentPlanet[$fields[Legacies_Empire::ID_SPECIAL_ANTIBALLISTIC_MISSILE]],
-                'limit'     => $this->_currentPlanet[$fields[Legacies_Empire::ID_BUILDING_MISSILE_SILO]] * 10
-                ),
-            Legacies_Empire::ID_SPECIAL_INTERPLANETARY_MISSILE => array(
-                'current'   => $this->_currentPlanet[$fields[Legacies_Empire::ID_SPECIAL_INTERPLANETARY_MISSILE]],
-                'requested' => $this->_currentPlanet[$fields[Legacies_Empire::ID_SPECIAL_INTERPLANETARY_MISSILE]],
-                'limit'     => $this->_currentPlanet[$fields[Legacies_Empire::ID_BUILDING_MISSILE_SILO]] * 5
-                )
-            );
-
-        if (in_array($shipId, array_keys($limitedElementsQty))) {
-            foreach ($this->_queue as $element) {
-                if ($element['ship_id'] != $shipId) {
-                    continue;
-                }
-
-                $limitedElementsQty[$shipId]['requested'] = Math::add($limitedElementsQty[$shipId]['requested'], $element['qty']);
-                if (Math::comp($limitedElementsQty[$shipId]['requested'], $limitedElementsQty[$shipId]['limit']) >= 0) {
-                    return 0;
-                }
-            }
-            if (Math::comp($limitedElementsQty[$shipId]['current'], $limitedElementsQty[$shipId]['limit']) >= 0) {
-                return 0;
-            }
-            if (Math::comp($qty, $limitedElementsQty[$shipId]['limit']) >= 0) {
-                return $limitedElementsQty[$shipId]['limit'];
-            }
-        }
-
-        return $qty;
+        return $this->_builder->getMaximumBuildableElementsCount($shipId);
     }
 
-    protected function _getResourcesNeeded($shipId, $qty)
+    public function getResourcesNeeded($shipId, $qty)
     {
-        $prices = Legacies_Empire_Model_Game_Prices::getSingleton();
-
-        $resourcesNeeded = array();
-        foreach ($this->_resourcesTypes as $resourceId) {
-            if (isset($prices[$shipId]) && isset($prices[$shipId][$resourceId]) && $prices[$shipId][$resourceId] > 0) {
-                $resourcesNeeded[$resourceId] = Math::mul($prices[$shipId][$resourceId], $qty);
-            }
-        }
-
-        return $resourcesNeeded;
+        return $this->_builder->getResourcesNeeded();
     }
 
     public function getBuildTime($shipId, $qty)
     {
-        $prices = Legacies_Empire_Model_Game_Prices::getSingleton();
-        $fields = Legacies_Empire_Model_Game_FieldsAlias::getSingleton();
-        $types = Legacies_Empire_Model_Game_Types::getSingleton();
-        $gameConfig = Legacies_Core_Model_Config::getSingleton();
-
-        $scale = 30;
-
-        $totalCost = Math::mul(Math::add($prices[$shipId][Legacies_Empire::RESOURCE_METAL], $prices[$shipId][Legacies_Empire::RESOURCE_CRISTAL]), $qty, $scale);
-        $speedFactor = $gameConfig->getData('game_speed');
-
-        $shipyardSpeedup = Math::div(1, Math::add($this->_currentPlanet[$fields[Legacies_Empire::ID_BUILDING_SHIPYARD]], 1, $scale), $scale);
-        $naniteSpeedup = Math::pow(.5, $this->_currentPlanet[$fields[Legacies_Empire::ID_BUILDING_NANITE_FACTORY]], $scale);
-        $structuresSpeedup = Math::mul($shipyardSpeedup, $naniteSpeedup, $scale);
-
-        $officerSpeedup = 1;
-        if (in_array($shipId, $types[Legacies_Empire::TYPE_SHIP])) {
-            $officerSpeedup = 1 - ($this->_currentUser['rpg_technocrate'] * .05);
-        } else if (in_array($shipId, $types[Legacies_Empire::TYPE_SPECIAL])) {
-            $officerSpeedup = 1 - ($this->_currentUser['rpg_technocrate'] * .05);
-        } else if (in_array($shipId, $types[Legacies_Empire::TYPE_DEFENSE])) {
-            $officerSpeedup = 1 - ($this->_currentUser['rpg_defenseur'] * .375);
-        }
-
-        $baseTime = ($totalCost / $speedFactor) * $structuresSpeedup;
-
-        return $baseTime * $officerSpeedup * 3600;
+        $this->_builder->getBuildTime($shipId, $qty);
     }
 
     public static function planetUpdateListener($eventData)
diff --git a/includes/application/code/community/Legacies/Empire/Model/Planet/Building/Shipyard/Builder.php b/includes/application/code/community/Legacies/Empire/Model/Planet/Building/Shipyard/Builder.php
index ab36ce5..101d232 100644
--- a/includes/application/code/community/Legacies/Empire/Model/Planet/Building/Shipyard/Builder.php
+++ b/includes/application/code/community/Legacies/Empire/Model/Planet/Building/Shipyard/Builder.php
@@ -3,20 +3,268 @@
 class Legacies_Empire_Model_Planet_Building_Shipyard_Builder
     extends Legacies_Empire_Model_BuilderAbstract
 {
-    public function __construct($currentPlanet, $currentUser)
+    public function init()
     {
-        parent::__construct($currentPlanet, $currentUser);
-
-        $this->_unserializeQueue($currentPlanet->getData('b_hangar_id'));
+        $this->_unserializeQueue($this->_currentPlanet->getData('b_hangar_id'));
     }
 
-    public function _initItem($shipId, $qty)
+    /**
+     * @param int $buildingId
+     * @param int $qty
+     * @param int $time
+     */
+    public function _initItem()
     {
+        $shipId = func_get_arg(0);
+        $qty = func_get_arg(1);
+        $time = func_get_arg(2);
+
         return new Legacies_Empire_Model_Planet_Building_Shipyard_Item(array(
             'ship_id'    => $shipId,
             'qty'        => $qty,
-            'created_at' => time(),
-            'updated_at' => time()
+            'created_at' => $time,
+            'updated_at' => $time
             ));
     }
-}
\ No newline at end of file
+
+    /**
+     * Check if a ship or defense type is actually buildable on the current
+     * planet, depending on the technology and buildings requirements.
+     *
+     * @param int $shipId
+     * @return bool
+     */
+    public function checkAvailability($shipId)
+    {
+        $types = Legacies_Empire_Model_Game_Types::getSingleton();
+        $requirements = Legacies_Empire_Model_Game_Requirements::getSingleton();
+
+        if (!isset($requirements[$shipId]) || empty($requirements[$shipId])) {
+            return true;
+        }
+
+        foreach ($requirements[$shipId] as $requirement => $level) {
+            if ($types->is($requirement, Legacies_Empire::TYPE_BUILDING) && $this->_currentPlanet->hasElement($requirement, $level)) {
+                continue;
+            } else if ($types->is($requirement, Legacies_Empire::TYPE_RESEARCH) && $this->_currentUser->hasElement($requirement, $level)) {
+                continue;
+            } else if ($types->is($requirement, Legacies_Empire::TYPE_DEFENSE) && $this->_currentPlanet->hasElement($requirement, $level)) {
+                continue;
+            } else if ($types->is($requirement, Legacies_Empire::TYPE_SHIP) && $this->_currentPlanet->hasElement($requirement, $level)) {
+                continue;
+            }
+            return false;
+        }
+
+        try {
+            // Dispatch event. Throw an exception to break the avaliability.
+            Legacies::dispatchEvent('planet.shipyard.check-availability', array(
+                'ship_id'  => $shipId,
+                'shipyard' => $this,
+                'planet'   => $this->_currentPlanet,
+                'user'     => $this->_currentUser
+                ));
+        } catch (Exception $e) {
+            return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * Returns the maximum quantity of elements that are possible to build on
+     * the current planet.
+     *
+     * @param int $shipId
+     * @return int|string
+     */
+    public function getMaximumBuildableElementsCount($shipId)
+    {
+        $prices = Legacies_Empire_Model_Game_Prices::getSingleton();
+        $fields = Legacies_Empire_Model_Game_FieldsAlias::getSingleton();
+
+        $resources = array(
+            Legacies_Empire::RESOURCE_METAL,
+            Legacies_Empire::RESOURCE_CRISTAL,
+            Legacies_Empire::RESOURCE_DEUTERIUM,
+            Legacies_Empire::RESOURCE_ENERGY
+            );
+
+        $qty = 0;
+        foreach ($resources as $resourceId) {
+            if (isset($prices[$shipId]) && isset($prices[$shipId][$resourceId]) && Math::comp($prices[$shipId][$resourceId], 0) > 0) {
+                $maxQty = Math::floor(Math::div($this->_currentPlanet->getData($resourceId), $prices[$shipId][$resourceId]));
+
+                if ($maxQty == 0) {
+                    return 0;
+                }
+
+                if ($qty == 0 || Math::comp($maxQty, $qty) < 0) {
+                    $qty = $maxQty;
+                }
+            }
+        }
+
+        if ($qty == 0) {
+            return 0;
+        }
+
+        $limitedElementsQty = array(
+            Legacies_Empire::ID_DEFENSE_SMALL_SHIELD_DOME      => array(
+                'current'   => $this->_currentPlanet[$fields[Legacies_Empire::ID_DEFENSE_SMALL_SHIELD_DOME]],
+                'requested' => $this->_currentPlanet[$fields[Legacies_Empire::ID_DEFENSE_SMALL_SHIELD_DOME]],
+                'limit'     => 1
+                ),
+            Legacies_Empire::ID_DEFENSE_LARGE_SHIELD_DOME      => array(
+                'current'   => $this->_currentPlanet[$fields[Legacies_Empire::ID_DEFENSE_LARGE_SHIELD_DOME]],
+                'requested' => $this->_currentPlanet[$fields[Legacies_Empire::ID_DEFENSE_LARGE_SHIELD_DOME]],
+                'limit'     => 1
+                ),
+            Legacies_Empire::ID_SPECIAL_ANTIBALLISTIC_MISSILE  => array(
+                'current'   => $this->_currentPlanet[$fields[Legacies_Empire::ID_SPECIAL_ANTIBALLISTIC_MISSILE]],
+                'requested' => $this->_currentPlanet[$fields[Legacies_Empire::ID_SPECIAL_ANTIBALLISTIC_MISSILE]],
+                'limit'     => $this->_currentPlanet[$fields[Legacies_Empire::ID_BUILDING_MISSILE_SILO]] * 10
+                ),
+            Legacies_Empire::ID_SPECIAL_INTERPLANETARY_MISSILE => array(
+                'current'   => $this->_currentPlanet[$fields[Legacies_Empire::ID_SPECIAL_INTERPLANETARY_MISSILE]],
+                'requested' => $this->_currentPlanet[$fields[Legacies_Empire::ID_SPECIAL_INTERPLANETARY_MISSILE]],
+                'limit'     => $this->_currentPlanet[$fields[Legacies_Empire::ID_BUILDING_MISSILE_SILO]] * 5
+                )
+            );
+
+        if (in_array($shipId, array_keys($limitedElementsQty))) {
+            foreach ($this->_queue as $element) {
+                if ($element['ship_id'] != $shipId) {
+                    continue;
+                }
+
+                $limitedElementsQty[$shipId]['requested'] = Math::add($limitedElementsQty[$shipId]['requested'], $element['qty']);
+                if (Math::comp($limitedElementsQty[$shipId]['requested'], $limitedElementsQty[$shipId]['limit']) >= 0) {
+                    return 0;
+                }
+            }
+            if (Math::comp($limitedElementsQty[$shipId]['current'], $limitedElementsQty[$shipId]['limit']) >= 0) {
+                return 0;
+            }
+            if (Math::comp($qty, $limitedElementsQty[$shipId]['limit']) >= 0) {
+                return $limitedElementsQty[$shipId]['limit'];
+            }
+        }
+
+        return $qty;
+    }
+
+    /**
+     * Returns the time needed to build $qty of $shipId
+     *
+     * @param int $shipId
+     * @param int $qty
+     */
+    public function getBuildingTime($shipId, $qty)
+    {
+        $prices = Legacies_Empire_Model_Game_Prices::getSingleton();
+        $fields = Legacies_Empire_Model_Game_FieldsAlias::getSingleton();
+        $types = Legacies_Empire_Model_Game_Types::getSingleton();
+        $gameConfig = Legacies_Core_Model_Config::getSingleton();
+
+        Math::setPrecision(50);
+
+         // FIXME: Resource dependency
+        $totalCost = Math::mul(Math::add($prices[$shipId][Legacies_Empire::RESOURCE_METAL], $prices[$shipId][Legacies_Empire::RESOURCE_CRISTAL]), $qty);
+        $speedFactor = $gameConfig->getData('game_speed');
+
+        // FIXME: Building dependency
+        $shipyardSpeedup = Math::div(1, Math::add($this->_currentPlanet[$fields[Legacies_Empire::ID_BUILDING_SHIPYARD]], 1));
+        $naniteSpeedup = Math::pow(.5, $this->_currentPlanet[$fields[Legacies_Empire::ID_BUILDING_NANITE_FACTORY]]);
+        $structuresSpeedup = Math::mul($shipyardSpeedup, $naniteSpeedup);
+
+        // FIXME: officers
+        $officerSpeedup = 1;
+        if ($types->is($shipId, Legacies_Empire::TYPE_SHIP)) {
+            $officerSpeedup = 1 - ($this->_currentUser['rpg_technocrate'] * .05);
+        } else if ($types->is($shipId, Legacies_Empire::TYPE_SPECIAL)) {
+            $officerSpeedup = 1 - ($this->_currentUser['rpg_technocrate'] * .05);
+        } else if ($types->is($shipId, Legacies_Empire::TYPE_DEFENSE)) {
+            $officerSpeedup = 1 - ($this->_currentUser['rpg_defenseur'] * .375);
+        }
+
+        Math::setPrecision();
+
+        $baseTime = ($totalCost / $speedFactor) * $structuresSpeedup;
+
+        return (int) Math::floor($baseTime * $officerSpeedup * 3600);
+    }
+
+    /**
+     * (non-PHPdoc)
+     * @see Legacies_Empire_Model_BuilderAbstract::getResourcesNeeded()
+     */
+    public function getResourcesNeeded($shipId, $qty)
+    {
+        $prices = Legacies_Empire_Model_Game_Prices::getSingleton();
+
+        $resourcesNeeded = array();
+        foreach ($this->_resourcesTypes as $resourceId) {
+            if (isset($prices[$shipId]) && isset($prices[$shipId][$resourceId]) && $prices[$shipId][$resourceId] > 0) {
+                $resourcesNeeded[$resourceId] = Math::mul($prices[$shipId][$resourceId], $qty);
+            }
+        }
+
+        return $resourcesNeeded;
+    }
+
+    /**
+     * Update the contruction queue.
+     *
+     * @return Legacies_Empire_Model_Planet_Building_Shipyard
+     */
+    public function updateQueue($time = null)
+    {
+        $fields = Legacies_Empire_Model_Game_FieldsAlias::getSingleton();
+
+        if ($time === null) {
+            $time = Legacies::now();
+        }
+        $elapsedTime = $time - $this->_currentPlanet->getLastUpdate();
+
+        // Dispatch event
+        Legacies::dispatchEvent('planet.shipyard.update-queue.before', array(
+            'shipyard' => $this,
+            'planet'   => $this->_currentPlanet,
+            'user'     => $this->_currentUser
+            ));
+
+
+        foreach ($this as $element) {
+            $shipId = $element->getData('ship_id');
+            $qty = $element->getData('qty');
+            $buildTime = $this->getBuildingTime($shipId, $qty);
+
+            if ($elapsedTime >= $buildTime) {
+                $this->_currentPlanet[$fields[$shipId]] = Math::add($this->_currentPlanet[$fields[$shipId]], $qty);
+                $elapsedTime -= $buildTime;
+                $this->dequeue($element->getIndex());
+                continue;
+            }
+
+            $timeRatio = $elapsedTime / $buildTime;
+            $itemsBuilt = Math::mul($timeRatio, $qty);
+
+            $element->setData('updated_at', $time);
+            $element->setData('qty', Math::sub($qty, $itemsBuilt));
+            $this->_currentPlanet->setData($fields[$shipId], Math::add($this->_currentPlanet->getData($fields[$shipId]), $itemsBuilt));
+            break;
+        }
+
+        $this->_currentPlanet->setData('b_hangar_id', $this->serialize());
+
+        // Dispatch event
+        Legacies::dispatchEvent('planet.shipyard.update-queue.after', array(
+            'shipyard' => $this,
+            'planet'   => $this->_currentPlanet,
+            'user'     => $this->_currentUser
+            ));
+
+        return $this;
+    }
+};
\ No newline at end of file
diff --git a/includes/application/test/UpdatePlanet.php b/includes/application/test/UpdatePlanet.php
index bc772d5..fa5e8bc 100644
--- a/includes/application/test/UpdatePlanet.php
+++ b/includes/application/test/UpdatePlanet.php
@@ -9,7 +9,18 @@ if (!extension_loaded('xdebug')) {
 $planet = new Legacies_Empire_Model_Planet(array(
     'last_update'       => 0,
     'planet_type'       => 1,
-    'b_building'        => (3600 * 10000),
+
+    'b_hangar_id'       => serialize(array(array(
+            'ship_id'    => Legacies_Empire::ID_SHIP_LIGHT_TRANSPORT,
+            'qty'        => 1,
+            'created_at' => 0,
+            'updated_at' => 0
+        ), array(
+            'ship_id'    => Legacies_Empire::ID_SHIP_LARGE_TRANSPORT,
+            'qty'        => 100,
+            'created_at' => 600,
+            'updated_at' => 600
+        ))),
 
     'metal'             => 0,
     'metal_perhour'     => 20,
@@ -34,7 +45,7 @@ $planet = new Legacies_Empire_Model_Planet(array(
     'fusion_plant'         => 0,
     'robot_factory'        => 0,
     'nano_factory'         => 0,
-    'hangar'               => 0,
+    'hangar'               => 6,
     'metal_store'          => 5,
     'crystal_store'        => 5,
     'deuterium_store'      => 5,
@@ -46,11 +57,11 @@ var_dump($planet->getAllDatas());
 
 $planet->updateStorages(3600);
 
-var_dump($planet->getAllDatas());
+//var_dump($planet->getAllDatas());
 
 $planet->updateResourceProduction(3600);
 
-var_dump($planet->getAllDatas());
+//var_dump($planet->getAllDatas());
 
 Legacies::dispatchEvent('planet.update', array(
     'planet' => $planet,
@@ -59,7 +70,6 @@ Legacies::dispatchEvent('planet.update', array(
 
 var_dump($planet->getAllDatas());
 
-var_dump((3600 + (3600 * 200)));
 Legacies::dispatchEvent('planet.update', array(
     'planet' => $planet,
     'time'   => (3600 + (3600 * 200))