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Migration and Modernization Strategy Questions

Covers planning and executing large scale technology transformations such as migrating a monolithic application to microservices, replatforming from on premises to cloud, major framework or database upgrades, and full platform rearchitectures. Includes selection and justification of migration approaches and patterns for different business goals, for example strangler fig, forklift or lift and shift, incremental refactor, big bang replacement, parallel run, and coexistence strategies. Describes phasing and rollout planning to maintain product velocity, sequencing work to maximize business value, and staging and rollback plans to reduce operational and business risk. Addresses data migration planning, validation, consistency and synchronization approaches, testing and verification strategies to minimize downtime and customer impact, and fallback and rollback mechanisms. Covers engineering practices such as deployment automation, continuous integration and continuous delivery, observability and monitoring, and performance and capacity planning. Also includes architectural techniques such as application programming interface wrapping and adapter patterns to enable interoperability between legacy and new systems, governance and compliance considerations, security during migration, cross functional stakeholder communication and coordination, and how to define and measure success through key performance indicators and post migration validation.

MediumTechnical
58 practiced
During migration, how would you design a strategy to manage and migrate background jobs and batch processes that interact with transactional data? Address scheduling, idempotency, duplicate processing, ordering guarantees, and backpressure while switching execution platforms.
MediumSystem Design
67 practiced
You are the Cloud Architect for a company with 2M daily users and a monolith that peaks at 5,000 RPS and stores 5 TB of transactional data. The business requires 99.95% availability, RTO of 30 minutes and RPO of 5 minutes. Sketch a high-level migration plan to AWS microservices: outline phases, data sync approach, cutover strategy, rollback plan, and rough timeline and team composition.
MediumTechnical
58 practiced
Provide a framework to evaluate cost implications of migration choices (rehost, replatform, refactor). Include migration cost, run-rate cloud costs, engineering velocity impacts, expected savings, licensing differences, and recommend how to present total cost of ownership (TCO) to executives.
EasyTechnical
100 practiced
Compare the common migration approaches (lift-and-shift/forklift, replatform, refactor/rearchitect, rebuild, replace, and strangler-fig). For each approach explain: the typical business drivers that make it appropriate, primary technical trade-offs (risk, cost, time, technical debt), and one example scenario where you'd recommend it.
EasySystem Design
75 practiced
Explain the strangler-fig pattern. Describe a step-by-step plan to apply it to a legacy monolithic ecommerce application that handles product catalog, cart, checkout, and recommendations. State how you'd route traffic, migrate one capability at a time, and decommission the old code safely.

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