diff --git a/Backend/src/main/java/de/itsolutions/ticketsystem/config/DatabaseInitializer.java b/Backend/src/main/java/de/itsolutions/ticketsystem/config/DatabaseInitializer.java
new file mode 100644
index 0000000..0b4cc91
--- /dev/null
+++ b/Backend/src/main/java/de/itsolutions/ticketsystem/config/DatabaseInitializer.java
@@ -0,0 +1,36 @@
+package de.itsolutions.ticketsystem.config;
+
+import de.itsolutions.ticketsystem.service.AuthService;
+import org.springframework.boot.CommandLineRunner;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.jdbc.core.JdbcTemplate;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+@Configuration
+public class DatabaseInitializer {
+
+    private static final Logger logger = LoggerFactory.getLogger(DatabaseInitializer.class);
+
+    @Bean
+    public CommandLineRunner initDatabase(JdbcTemplate jdbcTemplate, AuthService authService) {
+        return args -> {
+            logger.info("Checking database schema...");
+            
+            // Add 'theme' column if it doesn't exist
+            try {
+                jdbcTemplate.execute("ALTER TABLE users ADD COLUMN IF NOT EXISTS theme VARCHAR(255) DEFAULT 'system' NOT NULL");
+                logger.info("Schema check: 'theme' column ensured.");
+            } catch (Exception e) {
+                logger.error("Error updating schema: " + e.getMessage());
+                // Continue, as it might fail if table locks exist, but we hope for the best or it's already there
+            }
+
+            // Run user data migration
+            logger.info("Running user migration...");
+            authService.migrateUsers();
+            logger.info("User migration completed.");
+        };
+    }
+}
diff --git a/Backend/src/main/java/de/itsolutions/ticketsystem/service/AuthService.java b/Backend/src/main/java/de/itsolutions/ticketsystem/service/AuthService.java
index 6b86d2e..d1dbfb2 100644
--- a/Backend/src/main/java/de/itsolutions/ticketsystem/service/AuthService.java
+++ b/Backend/src/main/java/de/itsolutions/ticketsystem/service/AuthService.java
@@ -85,7 +85,10 @@ public class AuthService {
      * Migrates existing user data, specifically populating firstname and lastname from the full name.
      * This method runs once after the application context is initialized.
      */
-    @jakarta.annotation.PostConstruct
+    /**
+     * Migrates existing user data, specifically populating firstname and lastname from the full name.
+     * This method is called by DatabaseInitializer on startup.
+     */
     public void migrateUsers() {
         List<User> users = userRepository.findAll();
         for (User user : users) {