<?xml version="1.0" encoding="UTF-8"?><rss version="2.0"><channel><title>Indresh Gahoi — Writing</title><description>Notes from production: distributed systems, banking platforms, and the staff-engineer path.</description><link>https://indreshgahoi.com/</link><item><title>Flash-Sale Ticket Booking System</title><link>https://indreshgahoi.com/blog/flash-sale-ticket-booking-system/</link><guid isPermaLink="true">https://indreshgahoi.com/blog/flash-sale-ticket-booking-system/</guid><description>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.</description><pubDate>Fri, 25 Sep 2026 00:00:00 GMT</pubDate><category>ticketing</category><category>system-design</category><category>distributed-systems</category><category>postgresql</category><category>redis</category><category>sre</category></item><item><title>Instagram Feed Generation System</title><link>https://indreshgahoi.com/blog/instagram-feed-generation-system/</link><guid isPermaLink="true">https://indreshgahoi.com/blog/instagram-feed-generation-system/</guid><description>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.</description><pubDate>Fri, 18 Sep 2026 00:00:00 GMT</pubDate><category>instagram</category><category>distributed-systems</category><category>sharding</category><category>system-design</category><category>kafka</category></item><item><title>Exactly-once effects on an at-least-once queue</title><link>https://indreshgahoi.com/blog/exactly-once-effects-on-an-at-least-once-queue/</link><guid isPermaLink="true">https://indreshgahoi.com/blog/exactly-once-effects-on-an-at-least-once-queue/</guid><description>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.</description><pubDate>Sun, 16 Aug 2026 00:00:00 GMT</pubDate><category>distributed-systems</category><category>aws</category><category>banking</category><category>idempotency</category></item></channel></rss>