diff --git a/test/orm/sql/StatementCacheTest.cpp b/test/orm/sql/StatementCacheTest.cpp
index 78d3713..e213cd5 100644
--- a/test/orm/sql/StatementCacheTest.cpp
+++ b/test/orm/sql/StatementCacheTest.cpp
@@ -22,54 +22,57 @@ using namespace matador::sql;
 using namespace matador::query;
 using namespace matador::utils;
 
-// Beispiel für einen Observer, der die Metriken auswertet
-// class MetricsObserver : public statement_cache_observer_interface {
-// public:
-//   void on_event(const statement_cache_event& evt) override {
-//     std::lock_guard<std::mutex> lock(mutex_);
-//
-//     switch (evt.type) {
-//       case statement_cache_event::Type::LockFailed:
-//         lock_failure_count_++;
-//         if (evt.duration) {
-//           total_lock_wait_time_ += evt.duration.value();
-//         }
-//         break;
-//
-//       case statement_cache_event::Type::ExecutionEnded:
-//         execution_count_++;
-//         if (evt.duration) {
-//           total_execution_time_ += evt.duration.value();
-//         }
-//         break;
-//     }
-//   }
-//
-//   // Metrik-Zugriffsmethoden
-//   double get_average_lock_wait_time() const {
-//     std::lock_guard<std::mutex> lock(mutex_);
-//     if (lock_failure_count_ == 0) return 0.0;
-//     return std::chrono::duration<double>(total_lock_wait_time_).count() / lock_failure_count_;
-//   }
-//
-//   double get_average_execution_time() const {
-//     std::lock_guard<std::mutex> lock(mutex_);
-//     if (execution_count_ == 0) return 0.0;
-//     return std::chrono::duration<double>(total_execution_time_).count() / execution_count_;
-//   }
-//
-//   size_t get_lock_failure_count() const {
-//     std::lock_guard<std::mutex> lock(mutex_);
-//     return lock_failure_count_;
-//   }
-//
-// private:
-//   mutable std::mutex mutex_;
-//   size_t lock_failure_count_{0};
-//   size_t execution_count_{0};
-//   std::chrono::nanoseconds total_lock_wait_time_{0};
-//   std::chrono::nanoseconds total_execution_time_{0};
-// };
+class MetricsObserver {
+public:
+  MetricsObserver(message_bus &bus) {
+
+  }
+  void on_event(const statement_cache_event& evt) override {
+    std::lock_guard<std::mutex> lock(mutex_);
+
+    switch (evt.type) {
+      case statement_cache_event::Type::LockFailed:
+        lock_failure_count_++;
+        if (evt.duration) {
+          total_lock_wait_time_ += evt.duration.value();
+        }
+        break;
+
+      case statement_cache_event::Type::ExecutionEnded:
+        execution_count_++;
+        if (evt.duration) {
+          total_execution_time_ += evt.duration.value();
+        }
+        break;
+    }
+  }
+
+  // Metrik-Zugriffsmethoden
+  double get_average_lock_wait_time() const {
+    std::lock_guard lock(mutex_);
+    if (lock_failure_count_ == 0) return 0.0;
+    return std::chrono::duration<double>(total_lock_wait_time_).count() / lock_failure_count_;
+  }
+
+  double get_average_execution_time() const {
+    std::lock_guard lock(mutex_);
+    if (execution_count_ == 0) return 0.0;
+    return std::chrono::duration<double>(total_execution_time_).count() / execution_count_;
+  }
+
+  size_t get_lock_failure_count() const {
+    std::lock_guard lock(mutex_);
+    return lock_failure_count_;
+  }
+
+private:
+  mutable std::mutex mutex_;
+  size_t lock_failure_count_{0};
+  size_t execution_count_{0};
+  std::chrono::nanoseconds total_lock_wait_time_{0};
+  std::chrono::nanoseconds total_execution_time_{0};
+};
+
 // void example_with_metrics() {
 //   connection_pool pool("noop://noop.db", 4);
 //   statement_cache cache(pool, 5);
@@ -304,9 +307,10 @@ TEST_CASE("Race condition simulation with mixed access", "[statement_cache][race
 
   auto task = [&](int /*id*/) {
     for (int i = 0; i < operations; ++i) {
-      auto sql = "SELECT " + std::to_string(i % 10);
-      auto result = cache.acquire({sql});
-      REQUIRE(result);
+      const auto sql = "SELECT " + std::to_string(i % 10);
+      if (const auto result = cache.acquire({sql}); !result) {
+        FAIL("Statement should not be available");
+      }
 
       // if (i % 50 == 0) {
         // cache.cleanup_expired_connections();