diff --git a/tests/integration/Features/FeaturesControllerTest.php b/tests/integration/Features/FeaturesControllerTest.php
new file mode 100644
index 0000000000..fe7f4ab4fd
--- /dev/null
+++ b/tests/integration/Features/FeaturesControllerTest.php
@@ -0,0 +1,71 @@
+<?php
+namespace MailPoet\Test\API\JSON\v1;
+
+use MailPoet\Features\FeaturesController;
+use MailPoet\Models\FeatureFlag;
+
+class FeaturesControllerTest extends \MailPoetTest {
+  /** @var array */
+  private $defaults_backup;
+
+  function _before() {
+    parent::_before();
+    FeatureFlag::deleteMany();
+    $this->defaults_backup = FeaturesController::$defaults;
+  }
+
+  function testItReturnsDefaults() {
+    FeaturesController::$defaults = [
+      'feature-a' => true,
+      'feature-b' => false,
+    ];
+
+    $controller = new FeaturesController();
+    expect($controller->isSupported('feature-a'))->equals(true);
+    expect($controller->isSupported('feature-b'))->equals(false);
+    expect($controller->getAllFlags())->equals([
+      'feature-a' => true,
+      'feature-b' => false,
+    ]);
+  }
+
+  function testItReturnsDatabaseValue() {
+    FeaturesController::$defaults = [
+      'feature-a' => true,
+    ];
+
+    FeatureFlag::createOrUpdate([
+      'name' => 'feature-a',
+      'value' => false,
+    ]);
+
+    $controller = new FeaturesController();
+    expect($controller->isSupported('feature-a'))->equals(false);
+    expect($controller->getAllFlags())->equals([
+      'feature-a' => false,
+    ]);
+  }
+
+  function testItDoesNotReturnUnknownFlag() {
+    FeaturesController::$defaults = [];
+
+    FeatureFlag::createOrUpdate([
+      'name' => 'feature-unknown',
+      'value' => true,
+    ]);
+
+    $controller = new FeaturesController();
+    try {
+      $controller->isSupported('feature-unknown');
+    } catch (\RuntimeException $e) {
+      expect($e->getMessage())->equals("Unknown feature 'feature-unknown'");
+    }
+    expect($controller->getAllFlags())->isEmpty();
+  }
+
+  function _after() {
+    parent::_before();
+    FeatureFlag::deleteMany();
+    FeaturesController::$defaults = $this->defaults_backup;
+  }
+}