diff --git a/Models/OrderSuggestionInterface.php b/Models/OrderSuggestionInterface.php
new file mode 100644
index 0000000..67a669b
--- /dev/null
+++ b/Models/OrderSuggestionInterface.php
@@ -0,0 +1,28 @@
+<?php
+/**
+ * Orange Management
+ *
+ * PHP Version 8.0
+ *
+ * @package   Modules\Purchase\Models
+ * @copyright Dennis Eichhorn
+ * @license   OMS License 1.0
+ * @version   1.0.0
+ * @link      https://orange-management.org
+ */
+declare(strict_types=1);
+
+namespace Modules\Purchase\Models;
+
+/**
+ * Order suggestion interface.
+ *
+ * @package Modules\Purchase\Models
+ * @license OMS License 1.0
+ * @link    https://orange-management.org
+ * @since   1.0.0
+ */
+interface OrderSuggestionInterface
+{
+
+}
diff --git a/OrderSuggestion/DefaultOrderSuggestion.php b/OrderSuggestion/DefaultOrderSuggestion.php
index c769fbe..156fa7f 100644
--- a/OrderSuggestion/DefaultOrderSuggestion.php
+++ b/OrderSuggestion/DefaultOrderSuggestion.php
@@ -14,107 +14,109 @@ declare(strict_types=1);
 
 namespace Modules\Purchase\OrderSuggestion;
 
+use Modules\Purchase\Models\OrderSuggestionInterface;
+
 /**
  * OMS order suggestion class
  *
- * @package Modules\Purchase\Models\OrderSuggestion
+ * @package Modules\Purchase\OrderSuggestion
  * @license OMS License 1.0
  * @link    https://orange-management.org
  * @since   1.0.0
  */
 final class DefaultOrderSuggestion implements OrderSuggestionInterface
 {
-	/**
-	 * Which data should be used to create the order suggestion?
-	 *
-	 * @var int
-	 * @since 1.0.0
-	 */
-	public int $suggestionType = OrderSuggestionType::HISTORIC;
+    /**
+     * Which data should be used to create the order suggestion?
+     *
+     * @var int
+     * @since 1.0.0
+     */
+    public int $suggestionType = OrderSuggestionType::HISTORIC;
 
-	/**
-	 * Comparison duration type.
-	 *
-	 * @var int
-	 * @since 1.0.0
-	 */
-	public int $historicComparisonDurationType = OrderSuggestionComparisonDurationType::ANNUAL;
+    /**
+     * Comparison duration type.
+     *
+     * @var int
+     * @since 1.0.0
+     */
+    public int $historicComparisonDurationType = OrderSuggestionComparisonDurationType::ANNUALY;
 
-	/**
-	 * How many years should used for the analysis.
-	 *
-	 * @var int
-	 * @since 1.0.0
-	 */
-	public int $historicComparisonDuration = 1;
+    /**
+     * How many years should used for the analysis.
+     *
+     * @var int
+     * @since 1.0.0
+     */
+    public int $historicComparisonDuration = 1;
 
-	/**
-	 * Which averaging method should be used?
-	 *
-	 * @var int
-	 * @since 1.0.0
-	 */
-	public int $historicAveragingMethod = OrderSuggestionAveragingMethod::MEAN;
+    /**
+     * Which averaging method should be used?
+     *
+     * @var int
+     * @since 1.0.0
+     */
+    public int $historicAveragingMethod = OrderSuggestionAveragingMethod::MEAN;
 
-	/**
-	 * What should the focus of the order suggestion be?
-	 *
-	 * @var int
-	 * @since 1.0.0
-	 */
-	public int $optimizationType = OrderSuggestionOptimizationType::PRICE;
+    /**
+     * What should the focus of the order suggestion be?
+     *
+     * @var int
+     * @since 1.0.0
+     */
+    public int $optimizationType = OrderSuggestionOptimizationType::PRICE;
 
-	/**
-	 * How greedy should the algorithm be?
-	 *
-	 * The number represents how many items in % can be bought in additon to the optimal stock quantity.
-	 *
-	 * Higher means more room for adjustments.
-	 *
-	 * @var int
-	 * @since 1.0.0
-	 */
-	public int $optimizationGreediness = 10;
+    /**
+     * How greedy should the algorithm be?
+     *
+     * The number represents how many items in % can be bought in additon to the optimal stock quantity.
+     *
+     * Higher means more room for adjustments.
+     *
+     * @var int
+     * @since 1.0.0
+     */
+    public int $optimizationGreediness = 10;
 
-	/**
-	 * For how many days would you like to have stock?
-	 *
-	 * Or in other words, higher means you need to order less often per year.
-	 *
-	 * Only relevant if OptimizationType::AVAILABILITY
-	 *
-	 * @var int
-	 * @since 1.0.0
-	 */
-	public int $optimizationDays = 0;
+    /**
+     * For how many days would you like to have stock?
+     *
+     * Or in other words, higher means you need to order less often per year.
+     *
+     * Only relevant if OptimizationType::AVAILABILITY
+     *
+     * @var int
+     * @since 1.0.0
+     */
+    public int $optimizationDays = 0;
 
-	/**
-	 * Maximum available budget.
-	 *
-	 * 0 = infinite budget
-	 *
-	 * If a budget is defined and the optimal order is > than the available budget,
-	 * the algorithm will try to order as many different items as possible.
-	 *
-	 * If not all items can be ordered will try to order the items with the highest profit.
-	 *
-	 * @var int
-	 * @since 1.0.0
-	 */
-	public int $maxAvailableBudget = 0;
+    /**
+     * Maximum available budget.
+     *
+     * 0 = infinite budget
+     *
+     * If a budget is defined and the optimal order is > than the available budget,
+     * the algorithm will try to order as many different items as possible.
+     *
+     * If not all items can be ordered will try to order the items with the highest profit.
+     *
+     * @var int
+     * @since 1.0.0
+     */
+    public int $maxAvailableBudget = 0;
 
-	/**
-	 * item data for algorithm:
-	 * 		number
-	 * 		name
-	 * 		purchase price per volume
-	 * 		minimum quantity per volume
-	 * 		delivery time / lead time
-	 * 		in-house processing time (e.g. qs time, labelling, packaging)
-	 * 		ordered (order confirmations)
-	 * 		stock available
-	 * 		offers
-	 * 		avg. profit
-	 * 		demand in period N
-	 */
+    /**
+     * item data for algorithm:
+     *         number
+     *         name
+     *         purchase price per volume
+     *         minimum quantity per volume
+     *         delivery time / lead time
+     *         in-house processing time (e.g. qs time, labelling, packaging)
+     *         ordered (order confirmations)
+     *         stock available
+     *         offers
+     *         avg. profit
+     *         demand in period N
+     */
 }
diff --git a/OrderSuggestion/OrderSuggestionAveragingMethod.php b/OrderSuggestion/OrderSuggestionAveragingMethod.php
index 9913bc6..0d24c18 100644
--- a/OrderSuggestion/OrderSuggestionAveragingMethod.php
+++ b/OrderSuggestion/OrderSuggestionAveragingMethod.php
@@ -4,7 +4,7 @@
  *
  * PHP Version 8.0
  *
- * @package   Modules\Purchase\Models\OrderSuggestion
+ * @package   Modules\Purchase\OrderSuggestion
  * @copyright Dennis Eichhorn
  * @license   OMS License 1.0
  * @version   1.0.0
@@ -19,7 +19,7 @@ use phpOMS\Stdlib\Base\Enum;
 /**
  * Suggestion type enum.
  *
- * @package Modules\Purchase\Models\OrderSuggestion
+ * @package Modules\Purchase\OrderSuggestion
  * @license OMS License 1.0
  * @link    https://orange-management.org
  * @since   1.0.0
diff --git a/OrderSuggestion/OrderSuggestionComparisonDurationType.php b/OrderSuggestion/OrderSuggestionComparisonDurationType.php
index e3b97c9..7f50279 100644
--- a/OrderSuggestion/OrderSuggestionComparisonDurationType.php
+++ b/OrderSuggestion/OrderSuggestionComparisonDurationType.php
@@ -4,7 +4,7 @@
  *
  * PHP Version 8.0
  *
- * @package   Modules\Purchase\Models\OrderSuggestion
+ * @package   Modules\Purchase\OrderSuggestion
  * @copyright Dennis Eichhorn
  * @license   OMS License 1.0
  * @version   1.0.0
@@ -19,7 +19,7 @@ use phpOMS\Stdlib\Base\Enum;
 /**
  * Suggestion type enum.
  *
- * @package Modules\Purchase\Models\OrderSuggestion
+ * @package Modules\Purchase\OrderSuggestion
  * @license OMS License 1.0
  * @link    https://orange-management.org
  * @since   1.0.0
diff --git a/OrderSuggestion/OrderSuggestionOptimizationType.php b/OrderSuggestion/OrderSuggestionOptimizationType.php
index 1e34bcc..3fcc27b 100644
--- a/OrderSuggestion/OrderSuggestionOptimizationType.php
+++ b/OrderSuggestion/OrderSuggestionOptimizationType.php
@@ -4,7 +4,7 @@
  *
  * PHP Version 8.0
  *
- * @package   Modules\Purchase\Models\OrderSuggestion
+ * @package   Modules\Purchase\OrderSuggestion
  * @copyright Dennis Eichhorn
  * @license   OMS License 1.0
  * @version   1.0.0
@@ -19,7 +19,7 @@ use phpOMS\Stdlib\Base\Enum;
 /**
  * Suggestion type enum.
  *
- * @package Modules\Purchase\Models\OrderSuggestion
+ * @package Modules\Purchase\OrderSuggestion
  * @license OMS License 1.0
  * @link    https://orange-management.org
  * @since   1.0.0
diff --git a/OrderSuggestion/OrderSuggestionType.php b/OrderSuggestion/OrderSuggestionType.php
index cb8ced6..891eccc 100644
--- a/OrderSuggestion/OrderSuggestionType.php
+++ b/OrderSuggestion/OrderSuggestionType.php
@@ -4,7 +4,7 @@
  *
  * PHP Version 8.0
  *
- * @package   Modules\Purchase\Models\OrderSuggestion
+ * @package   Modules\Purchase\OrderSuggestion
  * @copyright Dennis Eichhorn
  * @license   OMS License 1.0
  * @version   1.0.0
@@ -19,7 +19,7 @@ use phpOMS\Stdlib\Base\Enum;
 /**
  * Suggestion type enum.
  *
- * @package Modules\Purchase\Models\OrderSuggestion
+ * @package Modules\Purchase\OrderSuggestion
  * @license OMS License 1.0
  * @link    https://orange-management.org
  * @since   1.0.0
diff --git a/composer.json b/composer.json
index be46f49..0bf301c 100755
--- a/composer.json
+++ b/composer.json
@@ -9,7 +9,7 @@
     ],
     "require-dev": {
         "phpunit/phpunit": ">=9.4",
-        "friendsofphp/php-cs-fixer": ">=2.18",
+        "friendsofphp/php-cs-fixer": ">=3.0",
         "squizlabs/php_codesniffer": ">=3.5",
         "phpmd/phpmd": ">=2.9",
         "phpstan/phpstan": ">=0.12.58",