App Modernization: Demystifying Distributed Transactions in Microservices with Saga Pattern and Achieving Data Integrity

Modernizing applications often involves transitioning from monolithic architectures to microservices, introducing complexities in maintaining data consistency across independent services. In a traditional monolithic application, a single database transaction can ensure all related operations either succeed or fail together. This also leads to bottleneck in scaling the system when load on the system increases, with leads to resource contention and affects the reliability of whole eco- system. Traditional single-database transactions are no longer feasible, necessitating solutions for distributed transactions and with the adoption of cloud-native environments. This paper explores the Saga design pattern as a key strategy for managing such transactions in modernized applications, particularly within the banking and fintech sectors. The Saga pattern addresses scalability and reliability challenges by decomposing complex business processes into sequences of local transactions with compensating mechanisms for failures, thereby ensuring eventual data consistency in distributed systems. This approach “demystifies” the intricacies of data integrity in microservice environments, a crucial aspect of successful application modernization. Given the paramount importance of data integrity and regulatory compliance within the banking and fintech industries, this pattern offers a resilient and scalable solution for managing transactional workflows in distributed environments.