diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index afc726a..420b017 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -37,6 +37,10 @@ jobs:
                 name: Composer validate
                 run: composer validate --strict --ansi
 
+            -
+                name: Run Psalm
+                run: vendor/bin/psalm src --no-progress
+
             -
                 name: Run tests
                 run: vendor/bin/behat -f progress --strict -vvv --no-interaction --colors
diff --git a/composer.json b/composer.json
index 75e38bd..58a4728 100644
--- a/composer.json
+++ b/composer.json
@@ -14,11 +14,8 @@
         "behat/behat": "^3.4"
     },
     "require-dev": {
-        "friends-of-behat/cross-container-extension": "^1.0",
-        "friends-of-behat/test-context": "^1.0"
-    },
-    "suggest": {
-        "friends-of-behat/cross-container-extension": "^1.0"
+        "friends-of-behat/test-context": "^1.2",
+        "vimeo/psalm": "4.1.1"
     },
     "autoload": {
         "psr-4": {
diff --git a/features/not_crashing_behat_with_cross_container_extension.feature b/features/not_crashing_behat_with_cross_container_extension.feature
deleted file mode 100644
index 6056f40..0000000
--- a/features/not_crashing_behat_with_cross_container_extension.feature
+++ /dev/null
@@ -1,17 +0,0 @@
-Feature: Usage of ServiceContainerExtension together with CrossContainerExtension
-    In order to reference cross-container services and parameters inside Behat container
-    As a Behat User
-    I need to use ServiceContainerExtension and CrossContainerExtension together
-
-    Scenario: Not crashing Behat
-        Given a Behat configuration containing:
-        """
-        default:
-            extensions:
-                FriendsOfBehat\ServiceContainerExtension: ~
-
-                FriendsOfBehat\CrossContainerExtension: ~
-        """
-        And a feature file with passing scenario
-        When I run Behat
-        Then it should pass
diff --git a/psalm.xml b/psalm.xml
new file mode 100644
index 0000000..3e4e3d0
--- /dev/null
+++ b/psalm.xml
@@ -0,0 +1,15 @@
+<?xml version="1.0"?>
+<psalm
+    errorLevel="4"
+    resolveFromConfigFile="true"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xmlns="https://getpsalm.org/schema/config"
+    xsi:schemaLocation="https://getpsalm.org/schema/config vendor/vimeo/psalm/config.xsd"
+>
+    <projectFiles>
+        <directory name="src" />
+        <ignoreFiles>
+            <directory name="vendor" />
+        </ignoreFiles>
+    </projectFiles>
+</psalm>
diff --git a/src/ServiceContainer/ServiceContainerExtension.php b/src/ServiceContainer/ServiceContainerExtension.php
index b5a066f..fe42924 100644
--- a/src/ServiceContainer/ServiceContainerExtension.php
+++ b/src/ServiceContainer/ServiceContainerExtension.php
@@ -32,11 +32,6 @@
  */
 final class ServiceContainerExtension implements Extension
 {
-    /**
-     * @var CompilerPassInterface|null
-     */
-    private $crossContainerProcessor;
-
     /**
      * {@inheritdoc}
      */
@@ -50,12 +45,7 @@ public function getConfigKey(): string
      */
     public function initialize(ExtensionManager $extensionManager): void
     {
-        /** @var CrossContainerExtension $extension */
-        $extension = $extensionManager->getExtension('fob_cross_container');
 
-        if (null !== $extension) {
-            $this->crossContainerProcessor = $extension->getCrossContainerProcessor();
-        }
     }
 
     /**
@@ -90,9 +80,7 @@ public function load(ContainerBuilder $container, array $config): void
      */
     public function process(ContainerBuilder $container): void
     {
-        if (null !== $this->crossContainerProcessor) {
-            $this->crossContainerProcessor->process($container);
-        }
+
     }
 
     private function createLoader(ContainerBuilder $container, array $config): LoaderInterface