APIs, Networking & Integration Topics
API design, management, and integration patterns including REST, GraphQL, and other protocols. Covers API contract design, versioning strategies, error handling, idempotency, deprecation planning, and SDK/integration frameworks. Includes system-to-system integration, webhook patterns, and integration platform considerations. Excludes network infrastructure and network-layer protocols (see Network Architecture under Cloud & Infrastructure or a dedicated networking category if needed).
Application Programming Interface Design and Integration
Designing Application Programming Interfaces and selecting communication protocols to meet functional and non functional requirements. Candidates should be able to evaluate and choose between Representational State Transfer style resource oriented interfaces, Graph Query Language approaches, remote procedure call frameworks such as Google Remote Procedure Call, and message based or event driven integration patterns. Discussion should cover protocol and format trade offs including latency, throughput, consistency and ordering, binary versus text serialization formats such as protocol buffers or JavaScript Object Notation, developer ergonomics, client diversity, and resource consumption. Core design topics include contract design and schema evolution, versioning and backward compatibility strategies, pagination, filtering, sorting and error handling conventions, authentication and authorization models, rate limiting and quota strategies, caching choices, and gateway or proxy patterns. Integration concerns include direct synchronous calls, asynchronous message based decoupling, event streaming, and web hooks, plus client and server software development kits and data transformation between layers. Candidates should also explain resilience and reliability patterns such as timeouts, retries, circuit breaker and bulkhead techniques, and describe testing, monitoring and observability approaches including logging, metrics and distributed tracing. Finally, discussion should connect API and protocol choices to coupling, scalability, operational complexity, security posture, and developer productivity.
Enterprise Integration and Automation
Covers the end-to-end design, architecture, and operational management of connecting software systems across an enterprise, from hands-on technical implementation through vendor and governance decisions to production support. Candidates should be able to reason about integration architecture options (point-to-point, hub-and-spoke, enterprise service bus, publish-subscribe and event-driven architecture, and batch ETL pipelines), interface choices (APIs, messaging, streaming, and batch data exchange), and the trade-offs among latency, throughput, delivery semantics, and complexity. Data concerns include data flow mapping, data quality and reconciliation, master data management, schema evolution, and data governance and privacy. Strategic and operational concerns include migration and cutover planning, testing and rollback strategy, monitoring and observability of data flows, SLA and capacity planning, vendor selection and build-versus-buy trade-offs, and incident response. Implementation concerns include interface contract and version management, dependency and compatibility management, error handling and idempotency, reconciliation and eventual consistency, and diagnosing common integration failure modes such as protocol mismatches, schema drift, and version incompatibilities. Automation and workflow topics cover orchestration versus choreography, workflow automation to reduce manual effort, and the trade-offs between configuration and custom development. Candidates should be able to identify integration risks, propose mitigations, and reason about testing, monitoring, security, and continuous improvement for integrated systems, whether the question concerns hands-on implementation, architectural decision-making, or the business and governance side of an integration initiative.
API and Full Stack Coding Patterns
Beyond pure algorithms, be prepared for problems that combine algorithmic thinking with API design, rate limiting, caching strategies, or distributed system concepts. Understanding how a coding solution fits into a larger fullstack architecture.
Data Management and API Design
Designing how applications structure, expose, and consume data through APIs and backend systems. Covers API design principles for data endpoints, pagination, filtering and sorting, idempotency, versioning, rate limiting, schema design, normalization versus denormalization, consistency models, caching strategies, client side fetching patterns, and error handling. Includes considerations for data integrity across integrations, transactional boundaries, master data management, and how API decisions affect downstream consumers and performance.
Service Communication and API Design
Design and specify APIs and interservice communication patterns for systems that must scale. Topics include REST design and best practices, API versioning and deprecation strategies, backward compatibility and API evolution, contract design between services, choosing protocols such as gRPC versus HTTP for internal or external communication, security and authentication patterns at the API level, performance and scalability considerations, observability and monitoring of service interactions, and strategies for evolving interfaces without breaking consumers.
Application Programming Interface Design and Scalability
Designing application programming interfaces that remain reliable, performant, and maintainable at high scale. Candidates should understand how interface decisions affect scalability, availability, latency, and operational complexity and be able to reason about trade offs between client complexity and server responsibility. Core areas include stateless interface design, pagination and cursor strategies for large result sets, filtering and search optimization, payload minimization, batching and streaming, and techniques to reduce server load while preserving client experience. Resilience and operational controls include rate limiting and quota management, throttling, backpressure and flow control, retry semantics and idempotency patterns, error format design and explicit identification of retryable errors, and strategies for graceful degradation under overload. Evolution and compatibility topics include backward compatible versioning strategies, deprecation policies, contract design and testing approaches to avoid breaking consumers. Infrastructure and deployment considerations include API gateway and edge patterns, interaction with load balancers and traffic distribution, caching and content delivery, routing fault tolerance, health checks and canary rollout strategies, and observability through metrics, distributed tracing, and logging to support capacity planning and incident response. Security considerations such as scalable authentication and authorization, credential and key management, and permission models are also important. Candidates should be prepared to discuss concrete patterns, trade offs, algorithms, and operational playbooks for designing and running high traffic application programming interfaces.
Integration Patterns and API Design
Focuses on integration concepts, data flow, and API design as the foundation for connecting systems and services. Coverage includes data integration techniques such as ETL and ELT, change data capture, data warehousing, synchronization and eventual consistency challenges, latency and throughput considerations, middleware and messaging solutions, and common integration patterns used in marketing and enterprise stacks. For APIs, topics include what APIs are and why they matter for developer products, REST versus GraphQL trade offs and use cases, HTTP methods and semantics, authentication and authorization patterns, rate limiting and throttling, versioning strategies, idempotency and error handling, documentation and developer experience, monitoring and service level considerations, and how API choices affect product and business decisions.
Solution Architecture and System Integration
Designing end to end solutions that integrate multiple systems and services. Topics include API design and compatibility, protocol choices, data flow and transformation, middleware and orchestration, handling partial failures and eventual consistency, versioning and backward compatibility, and non functional requirements such as performance and security. Emphasis on mapping business requirements to technical solutions and integration strategies.
System Integration and Standards
Covers designing and integrating new systems to interoperate with existing infrastructure while adhering to or thoughtfully deviating from industry standards. Topics include understanding relevant standards such as federal information processing standards and transport layer security standards, handling cryptographic compatibility and algorithm agility, designing for graceful degradation and backward compatibility, managing version compatibility and breaking changes, application programming interface versioning strategies, data migration during upgrades, legacy system integration patterns, and clear upgrade and deprecation strategies. Also includes risk identification and mitigation for compatibility issues, testing and validation approaches for integration points, and security considerations when connecting disparate systems.