Topics
Java and JVM
Collections internals, concurrency, memory model, GC, virtual threads.
18 pagesSpring
IoC and AOP, Boot, JPA, transactions, caching, security, JWT, OAuth2.
25 pagesMicroservices
Gateway, resilience, saga, CQRS, outbox, observability.
10 pagesDatabases
Schema design, isolation and MVCC, SQL, sharding, NoSQL, migrations.
6 pagesMessaging
Kafka and RabbitMQ: groups, delivery, ordering, dead letters.
4 pagesDevOps and Cloud
Docker, Kubernetes, CI/CD, twelve-factor, deployments.
5 pagesSystem design
URL shortener, rate limiter, orders, notifications, trade-offs.
6 pagesInterview toolkit
Questions by level, STAR answers, coding problems, cheat sheets.
7 pages