pending

• Web app firewall
• Learn more about OSI model and what works in which layer
• Back of envelope estimation in SD
• CoDel Strategy in more detail
• WAL

Intermediate:

• Distributed rate limiting
• Leader election
• Distributed locking and lease expiry
• Quorum reads vs quorum writes
• Dead letter queues and poison messages
• Zero-downtime schema migration
• Circuit breaker and cascading failure control

Advanced:

• Split a monolith safely
• Multi-region failover
• Active-active conflict resolution
• Change Data Capture vs dual writes
• Search index freshness vs ranking quality
• Rebalancing shards under skewed traffic
• Noisy neighbor problem in multi-tenant systems
• Watermarks / late-arriving events in stream processing
• Exactly-once processing vs practical deduplication