Short, specific pieces on distributed systems, banking-grade correctness, and the staff-engineer path.
How I designed a flash-sale ticketing platform so that a stampede, a double sale and a phantom charge cannot happen: a technology-agnostic design, the reasoning behind each technology, a deep dive on the waiting room and lock strategy, and the SLOs to run it.
A system design walkthrough of an Instagram-style feed generation system I built as a runnable, actually-sharded implementation: requirements, invariants, API, schema, HLD, sequence diagrams, and real code from the repo for the hash ring and hot/cold tier caching.
A reference implementation in Java 21 / Spring Boot of the SQS + DynamoDB conditional-write pattern I use in production banking systems to stop duplicate deliveries from becoming duplicate debits.