https://www.khangnghiem.com/tags/distributed-systems/Recent content in Distributed-Systems on Khang NghiemHugoenTue, 03 Mar 2026 00:00:00 +0000https://www.khangnghiem.com/post/kafka-for-beginners/Tue, 03 Mar 2026 00:00:00 +0000https://www.khangnghiem.com/post/kafka-for-beginners/<p>Most explanations of Kafka start with &ldquo;Kafka is a distributed event streaming platform.&rdquo; That sentence is accurate and tells you nothing useful. This post starts from the problem Kafka was built to solve, then explains each piece of the system from why it exists, not from what it is called.</p> <hr> <h2 id="part-1-why-kafka-exists">Part 1: Why Kafka Exists</h2> <h3 id="the-problem-with-direct-service-calls">The problem with direct service calls</h3> <p>Suppose you have an e-commerce system. When a user places an order, several things must happen: the inventory service deducts stock, the notification service sends a confirmation email, the analytics service records the sale, and the fraud detection service runs a check.</p>