diff --git a/src/g2_2025_imu_reader_pkg/src/database/DatabaseManager.hpp b/src/g2_2025_imu_reader_pkg/src/database/DatabaseManager.hpp
index 1534d41..0a89bf5 100644
--- a/src/g2_2025_imu_reader_pkg/src/database/DatabaseManager.hpp
+++ b/src/g2_2025_imu_reader_pkg/src/database/DatabaseManager.hpp
@@ -31,7 +31,7 @@ public:
     void create_tables();
 
     // IMU Data operations
-    bool store_imu_data(
+    virtual bool store_imu_data(
         double linear_accel_x, double linear_accel_y, double linear_accel_z,
         double angular_vel_x, double angular_vel_y, double angular_vel_z
     );
diff --git a/src/g2_2025_imu_reader_pkg/src/imu_database_writer/nodes/IMUDatabaseWriter.cpp b/src/g2_2025_imu_reader_pkg/src/imu_database_writer/nodes/IMUDatabaseWriter.cpp
index e586fa2..0e93b4e 100644
--- a/src/g2_2025_imu_reader_pkg/src/imu_database_writer/nodes/IMUDatabaseWriter.cpp
+++ b/src/g2_2025_imu_reader_pkg/src/imu_database_writer/nodes/IMUDatabaseWriter.cpp
@@ -2,10 +2,15 @@
 
 namespace assignments::two::imu_database_writer {
 
-IMUDatabaseWriter::IMUDatabaseWriter()
+IMUDatabaseWriter::IMUDatabaseWriter(std::unique_ptr<DatabaseManager> db_manager)
     : Node("imu_database_writer")
 {
-    db_manager_ = std::make_unique<DatabaseManager>(this->get_logger());
+    // allow injection of mock database manager for tests
+    if (db_manager) {
+        db_manager_ = std::move(db_manager);
+    } else {
+        db_manager_ = std::make_unique<DatabaseManager>(this->get_logger());
+    }
 
     // Create subscriber for IMU data
     imu_subscriber_ = this->create_subscription<sensor_msgs::msg::Imu>(
diff --git a/src/g2_2025_imu_reader_pkg/src/imu_database_writer/nodes/IMUDatabaseWriter.hpp b/src/g2_2025_imu_reader_pkg/src/imu_database_writer/nodes/IMUDatabaseWriter.hpp
index 909e7ae..a3507f2 100644
--- a/src/g2_2025_imu_reader_pkg/src/imu_database_writer/nodes/IMUDatabaseWriter.hpp
+++ b/src/g2_2025_imu_reader_pkg/src/imu_database_writer/nodes/IMUDatabaseWriter.hpp
@@ -25,7 +25,7 @@ namespace assignments::two::imu_database_writer {
 
 class IMUDatabaseWriter : public rclcpp::Node {
 public:
-    IMUDatabaseWriter();
+    IMUDatabaseWriter(std::unique_ptr<DatabaseManager> db_manager = nullptr);
 
     void imu_data_callback(const sensor_msgs::msg::Imu::SharedPtr msg);