diff --git a/src/Fakes/ActivityFake.php b/src/Fakes/ActivityFake.php
new file mode 100644
index 0000000..d5f5639
--- /dev/null
+++ b/src/Fakes/ActivityFake.php
@@ -0,0 +1,38 @@
+<?php
+
+namespace Zoomyboy\LaravelNami\Fakes;
+
+use Illuminate\Support\Facades\Http;
+
+class ActivityFake extends Fake
+{
+    /**
+     * @param array<int, array{descriptor: string, id: int}> $data
+     */
+    public function fetches(int $groupId, array $data): self
+    {
+        Http::fake(function ($request) use ($data, $groupId) {
+            $url = "https://nami.dpsg.de/ica/rest/nami/taetigkeitaufgruppierung/filtered/gruppierung/gruppierung/{$groupId}";
+            if ($request->url() === $url && 'GET' === $request->method()) {
+                return $this->dataResponse($data);
+            }
+        });
+
+        return $this;
+    }
+
+    /**
+     * @param array<int, array{descriptor: string, id: int}> $data
+     */
+    public function fetchesSubactivity(int $activityId, array $data): self
+    {
+        Http::fake(function ($request) use ($data, $activityId) {
+            $url = "https://nami.dpsg.de/ica/rest/nami/untergliederungauftaetigkeit/filtered/untergliederung/taetigkeit/{$activityId}";
+            if ($request->url() === $url && 'GET' === $request->method()) {
+                return $this->dataResponse($data);
+            }
+        });
+
+        return $this;
+    }
+}