System Design
CAP, sharding, replication, caching, messaging, consensus, saga, CQRS, rate limiting, and end-to-end design problems (URL shortener, chat, news feed, ride-share, payments, video, and more).
JS / TypeScript
Event loop, closures, prototypes, async/await, generics, conditional types, React internals, performance, Node.js, Next.js.
Java
OOP, collections, concurrency, virtual threads, JVM internals, GC tuning, GraalVM, Spring Boot, Kafka integration, observability.
Apache Kafka
Brokers, partitions, consumer groups, KRaft, tiered storage, schema evolution, streams, hot partitions, DLQ, multi-DC.
Docker
Namespaces, cgroups, BuildKit, multi-arch, distroless, rootless, storage drivers, resource limits, PID 1, health checks.
Rust
Ownership, lifetimes, smart pointers, Send/Sync, async/Tokio, traits, closures, unsafe, anyhow/thiserror, testing.