What Is Saga Pattern?

The Saga pattern is a microservices design pattern that manages distributed transactions by splitting them into a sequence of local steps with compensating actions to maintain consistency if failures occur.

When to Use

Saga is used when a business process spans multiple services, such as order processing, payment, and shipping. It ensures each step can either succeed or be rolled back without needing a single global transaction.

Example

An e-commerce order might reserve stock, charge payment, and arrange delivery. If delivery fails, Saga automatically triggers compensations: refund payment and release stock.

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Why Is It Important

It ensures eventual consistency across services without a heavy global transaction manager, improving scalability and fault tolerance.

Interview Tips

Explain Saga simply (like the e-commerce example), then highlight compensation logic, eventual consistency, and how it differs from atomic transactions. Mention pros and cons to show depth.

Trade-offs

Pros: Higher resilience, service autonomy, and scalability. Cons: Added complexity, eventual consistency delays, and more code for compensations.