Which migration approach is typically faster initially for moving legacy apps to AWS, with the understanding that refactoring can follow later?

• A. Lift-and-shift (rehost).
• B. Refactor.
• C. Rebuild from scratch.
• D. Replace with SaaS.

Answer: (A)

Lifting and shifting an older application to AWS emphasizes moving the workload with minimal changes, so you can get it running in the cloud quickly. This approach avoids rewriting code, redesigning architectures, or migrating data models for cloud-native patterns. By rehost-ing the existing environment—provisioning comparable compute, storage, and networking in AWS and moving the artifacts as-is—you cut the upfront effort and risk, delivering a faster initial migration. Once the app is operating in AWS, you can plan modernization steps later, such as refactoring to take advantage of managed services or decomposing a monolith into microservices, but the first goal is speed and a functioning cloud footprint.

Refactoring, rebuilding from scratch, or replacing with SaaS all require substantial changes, design work, or vendor alignment, which extends the timeline compared to a straightforward lift-and-shift. Refactoring changes the codebase to leverage cloud-native features, rebuilding from scratch means starting over, and SaaS replacement involves rearchitecting business processes around a vendor solution.