All Articles
Technical deep-dives on algorithms, system design, networking, and distributed systems — organized by topic.
Data Structures & Algorithms
Binary Search — Concept
Binary search is not just searching in a sorted array. It's about finding a boundary in a monotonic decision space. Covers templates, invariants, and floating-point binary search.
Binary Search — Practice Questions
Curated list of 40+ binary search problems from LeetCode, GeeksforGeeks, Codeforces, and SPOJ — organized by pattern.
Heaps & Heapsort — One-shot notes
Priority Queue ADT, Binary Heap (max & min), Max_Heapify, Build_Max_Heap, HeapSort — complete walkthrough with demos, pseudocode, and complexity proofs.
Priority Queue — Practice Problems
A categorized list of easy, medium, and hard heap and priority queue interview problems.
Time & Space Complexity Analysis
Comprehensive guide to asymptotic analysis, Big-O, recurrences, Master Theorem, Akra–Bazzi, and amortized analysis — with mathematical methods and practice problems.
High Level Design
SSL / TLS Explained
HTTP vs HTTPS, TLS handshake, TLS 1.3, certificates & CAs, symmetric vs asymmetric encryption, AES-256, cipher suites, mTLS, attacks & mitigations, and best practices.
JWT & Auth
How JSON Web Tokens actually work — structure, signing and verification, auth flows, access and refresh tokens, and the security pitfalls, compiled into one unit.
Netflix Hollow — Deep Dive
How Netflix Hollow replicates a read-only, in-memory dataset from one producer to many consumers — snapshots, deltas, reverse deltas, ordinal-based columnar storage, producer/consumer lifecycle, and failure modes.
Dynamo: Amazon's Highly Available Key-value Store
Amazon's 2007 Dynamo paper — a decentralized, highly available key-value store: consistent hashing, vector clocks, sloppy quorums, hinted handoff, Merkle trees, and gossip-based membership.
Cluster Architecture — Building Up the Ring
Build a Cassandra cluster from one node up — naive partitioning, consistent hashing, virtual nodes (vnodes), replication, and rack-aware placement, derived from first principles.
Consistency
Tunable consistency in Cassandra — why different operations need different correctness, quorums, R + W > N, read repair, and consistency levels.
Cassandra Storage Engine Internals
Why Cassandra uses LSM trees instead of B-trees — memtables, SSTables, the commit log, compaction, bloom filters, and the read/write paths.
How Discord Stores Billions of Messages
How Discord scaled message storage to billions on Cassandra — data modeling, partitioning by bucket, and the operational lessons learned.
How Discord Stores Trillions of Messages
How Discord moved from Cassandra to ScyllaDB to store trillions of messages — GC pain, hot partitions, and a shard-per-core C++ rewrite.
Multi-Paxos Deep Dive
How Multi-Paxos elects a stable leader to turn single-value Paxos into an efficient, fault-tolerant log-replication engine for distributed databases.
Nginx Deep Dive
How NGINX serves hundreds of thousands of concurrent connections on modest hardware with a small pool of event-driven worker processes.
How Amazon S3 Works — Durability & Scale
How Amazon S3 reaches 11 nines of durability and serves over 1 PB/s by erasure-coding objects into shards spread across millions of cheap drives.
The October 2025 DynamoDB us-east-1 Outage
How a latent race condition in DynamoDB's automated DNS management emptied the us-east-1 endpoint's DNS record and cascaded into a ~14.5-hour AWS outage.
Dynamo & Bigtable Inheritance
How Cassandra inherits its cluster mechanics from Amazon Dynamo and its on-disk storage engine from Google Bigtable, replacing vector clocks with last-write-wins.
Cassandra Data Modeling & Anti-Patterns
Query-first data modeling in Cassandra — hot partitions, partition-size limits, common anti-patterns to avoid, and when not to use Cassandra.
Low Level Design
Mathematics
ML / Deep Learning
Embeddings — Introduction
An intuitive introduction to embeddings: fixed-length vectors that place items with similar meaning close together, learned by compressing raw data through a model.
Embeddings — Recommendation as a Business Problem
Why embeddings exist — recommendation and search as a business problem — and how machine learning turns users and items into vectors to surface the right content.
Computer Fundamentals
HTTP/1 Deep Dive
HTTP fundamentals, TCP relationship, keep-alive, pipelining, HOL blocking, domain sharding, and protocol overhead.
Data Flow In TCP
TCP flow control, slow-start, congestion avoidance, bandwidth-delay product, head-of-line blocking, connection reuse, and performance optimization strategies.
Building Blocks of TCP
OSI model, TCP/IP layers, TCP properties, 3-way & 4-way handshakes, keepalive, SYN flood & mitigation, TCP vs UDP, and port sharing.
HTTP/2 Deep Dive
HTTP/2 keeps HTTP semantics but changes how data is transported — binary frames, multiplexed streams, HPACK compression, server push, and flow control.
HTTP/3 Deep Dive
HTTP/3 keeps HTTP semantics but swaps the transport — running over QUIC on UDP to remove TCP head-of-line blocking, merge the TLS handshake for 1-RTT/0-RTT setup, and enable connection migration.
gRPC Deep Dive
Why gRPC's HTTP/2 transport, Protobuf binary serialization, and first-class streaming outperform REST for high-scale service-to-service communication.
QUIC Deep Dive
How QUIC folds reliability, multiplexed streams, congestion control, and built-in TLS 1.3 encryption into one UDP-based transport.
DevOps & Infrastructure
Understanding Docker Containers: A Complete Guide
Everything you need to know about Docker containers — from basic concepts to production deployment patterns and best practices.
Git Branching Strategies for Teams
Comparing GitFlow, GitHub Flow, and trunk-based development. Which branching strategy is right for your team?
General
REST API Design Best Practices
A practical guide to designing clean, consistent, and developer-friendly REST APIs. Covers naming, versioning, error handling, and pagination.
TypeScript Generics Explained Simply
Generics don't have to be confusing. A step-by-step guide with real-world examples to master TypeScript generics.