Systems design interview topics covered (that I remember). Note that you also need to know what product you'd choose and why and the trade offs of choosing that product over a different one. Web servers, Secrets management, Error reporting, Monitoring, Observability, logging/telemetry, Messaging services, Service workers and how to resolve bottlenecks, Database choices, Presigned URLs, Distributed systems, Encryption end to end, Caching, Load balancing, Blob storage (images), App servers, Microservices vs. monolith, Logging, Error reporting, MVP tradeoffs in development, Frontend framework choices, Reverse proxies, Eventual consistency, SQL vs. NoSQL, Queries and how to resolve slow ones, Event driven systems, Node and single threaded