Systems Architecture & Distributed Systems Topics
Large-scale distributed system design, service architecture, microservices patterns, global distribution strategies, scalability, and fault tolerance at the service/application layer. Covers microservices decomposition, caching strategies, API design, eventual consistency, multi-region systems, and architectural resilience patterns. Excludes storage and database optimization (see Database Engineering & Data Systems), data pipeline infrastructure (see Data Engineering & Analytics Infrastructure), and infrastructure platform design (see Cloud & Infrastructure).
Full Stack Architecture and Integration
Designing end to end application architecture across presentation, application programming interface layer, business logic, persistence, and infrastructure. Candidates should be able to reason about trade offs across frontend state management, client side processing versus server side work, API contract design, data modeling and database selection, caching strategies, offline and real time update mechanisms, observability and operational concerns, and how infrastructure choices constrain or enable patterns at each layer. Emphasis is on separation of concerns while recognizing when tighter integration is needed for performance, consistency, or reduced latency.
Trade Off Analysis and Decision Frameworks
Covers the practice of structured trade off evaluation and repeatable decision processes across product and technical domains. Topics include enumerating alternatives, defining evaluation criteria such as cost risk time to market and user impact, building scoring matrices and weighted models, running sensitivity or scenario analysis, documenting assumptions, surfacing constraints, and communicating clear recommendations with mitigation plans. Interviewers will assess the candidate's ability to justify choices logically, quantify impacts when possible, and explain governance or escalation mechanisms used to make consistent decisions.
Architecture and Technical Trade Offs
Centers on system and solution design decisions and the trade offs inherent in architecture choices. Candidates should be able to identify alternatives, clarify constraints such as scale cost and team capability, and articulate trade offs like consistency versus availability, latency versus throughput, simplicity versus extensibility, monolith versus microservices, synchronous versus asynchronous patterns, database selection, caching strategies, and operational complexity. This topic covers methods for quantifying or qualitatively evaluating impacts, prototyping and measuring performance, planning incremental migrations, documenting decisions, and proposing mitigation and monitoring plans to manage risk and maintainability.
Scalability and Performance
Focuses on capacity planning, performance tradeoffs, and strategies for handling growth. Topics include the relationship between latency, throughput, consistency, and availability, when to accept eventual consistency, vertical versus horizontal scaling, caching, sharding, load distribution, back pressure and throttling patterns, performance testing and benchmarking, capacity forecasting, and triggers for scaling decisions. Candidates should be able to identify bottlenecks, justify tradeoffs between cost and performance, and recommend mitigation approaches for common performance problems.
High Availability and Disaster Recovery
Designing systems to remain available and recoverable in the face of infrastructure failures, outages, and disasters. Candidates should be able to define and reason about Recovery Time Objective and Recovery Point Objective targets and translate service level agreement goals such as 99.9 percent to 99.999 percent into architecture choices. Core topics include redundancy strategies such as N plus one and N plus two, active active and active passive deployment patterns, multi availability zone and multi region topologies, and the trade offs between same region high availability and cross region disaster recovery. Discuss load balancing and traffic shaping, redundant load balancer design, and algorithms such as round robin, least connections, and consistent hashing. Explain failover detection, health checks, automated versus manual failover, convergence and recovery timing, and orchestration of failover and reroute. Cover backup, snapshot, and restore strategies, replication and consistency trade offs for stateful components, leader election and split brain mitigation, runbooks and recovery playbooks, disaster recovery testing and drills, and cost and operational trade offs. Include capacity planning, autoscaling, network redundancy, and considerations for security and infrastructure hardening so that identity, key management, and logging remain available and recoverable. Emphasize monitoring, observability, alerting for availability signals, and validation through chaos engineering and regular failover exercises.
System Design and Scalability
Covers architectural thinking and design tradeoffs for building reliable, high performance systems. Topics include design decision reasoning given constraints such as cost, latency and availability; scaling strategies including horizontal and vertical scaling, load balancing, caching patterns, database partitioning and sharding, read replicas, and asynchronous processing; capacity planning and observability; spotting and explaining bottlenecks such as hot partitions, single points of failure, database locks and network limits; and communicating technical impact in business terms. Candidates should be able to justify choices, compare alternatives, and articulate metrics and monitoring approaches to validate design decisions.
Trade-Off Analysis and Justification
Ability to identify key nonfunctional requirements and constraints and to compare alternative designs with clear, quantitative reasoning. Expect discussion of consistency versus availability, latency versus throughput, cost versus performance, operational complexity, and implementation risk. Candidates should demonstrate how to quantify trade offs using metrics such as latency percentiles, throughput, cost per request, and availability targets, how to choose appropriate consistency models and failure modes, and how to document and justify the selected architecture given product and business priorities.
Technical Debt and Scalability Considerations
Explain the concept of technical debt, its root causes, and the long term cost of quick fixes versus sustainable solutions. Discuss scalability considerations including capacity planning, performance bottlenecks, architecture patterns for horizontal scaling, caching and partitioning strategies, and the trade offs between rapid delivery and long term maintainability. Cover the role of automated testing, monitoring and observability, and prioritization frameworks for when to pay down debt versus when to accept it for business reasons.
System Design and Architecture Fundamentals
Comprehensive coverage of designing scalable, reliable, and maintainable software systems, combining foundational concepts, common architectural patterns, decomposition techniques, infrastructure design, and operational considerations. Candidates should understand core principles such as horizontal and vertical scaling, caching strategies and placement, data storage trade offs between relational structured query language databases and non relational databases, application programming interface design, load distribution and fault tolerance. They should be familiar with architectural styles and patterns including client server and layered architectures, monolithic and microservices decomposition, service oriented and event driven designs, gateway and proxy patterns, and resilience patterns such as circuit breakers and asynchronous processing. Assessment includes the ability to decompose a problem into logical components and layers, define component responsibilities, map data flows between ingestion processing storage and serving layers, and select appropriate infrastructure elements such as application servers caches message queues and database replication models. Interviewers evaluate estimation of scale and load and reasoning about trade offs such as consistency versus availability and partition tolerance latency versus throughput coupling versus cohesion and cost versus complexity, and the ability to justify architecture decisions. Candidates should be able to sketch high level designs, communicate architecture to technical and non technical stakeholders, propose migration paths such as when to combine or transition between patterns, and describe operational runbooks including failure mode mitigation monitoring observability and incident recovery. Practical topics include caching eviction policies such as least recently used and least frequently used load balancing approaches such as round robin and least connections rate limiting techniques replication and sharding strategies and design choices for synchronous request response versus asynchronous queue based messaging. Emphasis is on clarifying requirements estimating constraints proposing reasonable architectures and articulating trade offs and evolution paths rather than only low level implementation details.