Beginners
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HLD Fundamentals for Beginners: Estimation, Building Blocks and a Payments Lens
A beginner-friendly system design primer: the 6-step framework, back-of-envelope QPS math, L4 vs L7 load balancing, caching, databases, queues, reliability patterns and how a payment flows end to end.
7 min read
DSA Patterns Roadmap for Beginners: 9 Patterns With Runnable Java
Learn DSA as a small set of patterns instead of hundreds of problems. Nine patterns, each with a trigger phrase, a Java example you can run, complexity, and where it shows up in real design problems.
8 min read
LLD Series: DSA and Java Basics for LLD Interviews: A Gentle Primer for Beginners
If your DSA base feels shaky, read this first. It explains just the data structures, Big-O, concurrency and money rules that the LLD series actually uses, with runnable Java.
8 min read