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.
Integration Patterns and Messaging Systems
Understand approaches to integrating different systems: synchronous APIs, asynchronous messaging (queues, topics, events), batch processing, and data synchronization. Know when to use message queues vs. publish-subscribe vs. event streams. Understand the reliability patterns (acknowledgments, retries, dead-letter queues) and consistency implications. Know about API gateways, service discovery, and orchestration. Discuss trade-offs between tight coupling and loose coupling, and how integration choices affect system resilience.
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.
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.
API Integration and System Connectivity
Covers the end to end concepts and practices for connecting systems using application programming interfaces and integration middleware. Candidates should understand REST and HTTP fundamentals, webhooks versus polling, API authentication and authorization patterns, request and response formats, rate limiting, versioning, and reading API documentation. Include practical skills for building and troubleshooting integrations: data mapping and transformation, schema mapping, message formats, error handling and retry strategies, idempotency, logging and monitoring, and ensuring data consistency across synchronous and asynchronous flows. Also includes integration tooling and middleware platforms, real time versus batch synchronization, designing for partial failures and back pressure, and frontend concerns such as async data fetching, loading and error states, pagination, optimistic updates, and race condition mitigation.
Api Design and Versioning
Design and evolve application programming interfaces so they meet functional requirements while minimizing disruption to clients and services. Core skills include designing resource oriented endpoints, choosing and implementing versioning strategies, and preserving backward compatibility. Candidates should understand versioning approaches such as embedding a version in the endpoint path, using request headers to select versions, and designing non breaking changes so explicit version bumps are avoided. Important topics include idempotency, pagination, filtering, sorting, error response design, status semantics, rate limiting, authentication and authorization, and considerations for low bandwidth or mobile clients. At senior levels discuss operational and lifecycle concerns: deprecation policies and timelines, migration plans, compatibility testing, handling multiple client versions simultaneously in production, rolling deployments and coexistence strategies, contract testing, and alternatives such as remote procedure call frameworks. Expect trade off discussions around developer experience, client upgrade friction, monitoring and instrumentation for versioned traffic, and communication strategies with downstream consumers.
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.
Application Programming Interface Design and Strategy
Covers the design, developer experience, and strategic operating decisions for Application Programming Interfaces and developer platforms. Candidates should demonstrate core design principles such as simplicity, consistency, discoverability, clear naming and conventions, intuitive resource modeling, robust error handling, stability, backward compatibility, and explicit versioning strategies. They should understand trade offs among interface paradigms including Representational State Transfer style APIs, Graph Query Language approaches, and remote procedure call frameworks such as gRPC, and how those choices affect discoverability, latency, schema evolution, client ergonomics, testing, and mocking. The topic also includes the developer facing surface area beyond the interface itself: documentation, quickstart guides, sample code, software development kits, command line tools, interactive explorers, sandbox environments, and other onboarding artifacts that reduce friction. Candidates should be able to identify common friction points such as unclear documentation, complex setup and authentication flows, unhelpful error messages, inconsistent or surprising behaviors, slow feedback loops, and endpoints that are hard to mock or test, and propose concrete engineering and process solutions. Measurement and optimization expectations include onboarding and adoption metrics such as time to first successful call, time to first meaningful result, onboarding success rates, developer satisfaction and sentiment, adoption and churn, support and integration costs, error rates and latency, and how to instrument and monitor the developer journey. Engineering practices to discuss include stable contract design, semantic versioning and compatibility guarantees, schema and contract testing, clear deprecation policies, monitoring and observability for developer journeys, automated client generation and migration tooling, authentication and rate limiting strategies, webhook and event mechanisms, and monetization or partnership models for platform growth. Senior candidates should connect technical and experience decisions to product and business outcomes, explaining how design choices drive adoption, reduce support load, enable ecosystem growth, and preserve long term platform velocity, and should provide concrete examples of improvements implemented or proposed and how their impact was measured.
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.