HLD concepts, deep dives, and design patterns — my personal study notes
Distributed event streaming, partitions, consumer groups, replication, and real-world use cases.
In-memory data store, data structures, persistence, caching patterns, pub/sub, and Lua scripting.
Distributed search engine, inverted index, shards, mappings, query DSL, and aggregations.
Probabilistic data structures for set membership — false positives, hash functions, and 15 design use cases.
Cassandra vs PostgreSQL vs DynamoDB — when to use each, trade-offs, consistency models.
Sharding, partitioning, write-ahead logs, CQRS, and strategies for write-heavy workloads.
Read replicas, caching strategies, CDNs, database indexing, and denormalization patterns.
When to use serverless functions vs container orchestration — cost, cold starts, scalability trade-offs.
Back-of-envelope estimation, latency numbers every engineer should know, throughput reference tables.
OSI model, TCP/IP, DNS, HTTP/HTTPS, load balancing, CDN, and common interview networking questions.
Processes vs threads, scheduling, memory management, deadlocks, and concurrency primitives.