System Design Interview: Design a Load Balancer
4 min read System Design: Load Balancer — How to Design Traffic Distribution at Scale Load balancers are one of the most fundamental […] Read article
System Design
Algorithms
Graph Algorithms Interview Patterns: BFS, DFS, Dijkstra & Cycle Detection
5 min read Graph Algorithms Interview Patterns: BFS, DFS, Dijkstra & More Graph problems appear in roughly 25% of FAANG algorithm interviews. Mastering Read article
Algorithms
Math and Number Theory Interview Patterns: GCD, Primes, Modular Arithmetic
4 min read Why Math in Coding Interviews? Math problems appear in interviews at all levels — they test logical reasoning and knowledge Read article
System Design
System Design Interview: API Design (REST vs GraphQL vs gRPC)
4 min read Why API Design Matters in Interviews API design questions appear in senior system design interviews: “Design the Twitter API,” “Design Read article
System Design
Database Indexing Interview Guide: B-Trees, Composite Indexes, Query Optimization
5 min read Why Indexes Matter A database index is a data structure that enables fast lookup of rows without scanning the entire Read article
System Design
System Design Interview: Multi-Region Architecture and Global Replication
7 min read Why Multi-Region? Single-region deployments have two problems: (1) Latency — a user in Tokyo making a request to a US-East Read article
Algorithms
Concurrency Interview Patterns: Locks, Thread Safety, Producer-Consumer
7 min read Why Concurrency in Interviews? Concurrency problems appear at senior-level interviews (SDE-2 and above) at companies like Apple, Google, and Databricks. Read article
Algorithms
Sorting Algorithms Interview Guide: Quicksort, Mergesort, Counting Sort
5 min read Why Sorting Algorithms Matter in Interviews Sorting knowledge signals deep CS understanding. Interviewers ask about sorting to evaluate: time/space complexity Read article
System Design
System Design Interview: Time Series Database (Prometheus / InfluxDB)
6 min read What Is a Time Series Database? A time series database (TSDB) stores sequences of timestamped values — metrics, sensor readings, Read article
Algorithms
Hash Map Interview Patterns: Two Sum, Frequency Counting, Sliding Window
7 min read Why Hash Maps Are Fundamental Hash maps (dictionaries in Python, HashMaps in Java) provide O(1) average-case lookup, insertion, and deletion. Read article
System Design
System Design Interview: Object Storage (Amazon S3)
6 min read What Is Object Storage? Object storage stores unstructured data (images, videos, backups, logs) as discrete objects with a flat namespace Read article
System Design
System Design Interview: Notification Service (Push, SMS, Email at Scale)
6 min read Overview A notification service delivers time-sensitive messages to users via push notifications (mobile), SMS, email, and in-app alerts. WhatsApp sends Read article
Algorithms
Topological Sort Interview Patterns: Kahn’s Algorithm, DFS Ordering, Cycle Detection
7 min read What Is Topological Sort? A topological sort of a directed acyclic graph (DAG) produces a linear ordering of vertices such Read article
Algorithms
Matrix and Grid DP Interview Patterns: Unique Paths, Minimum Path Sum, Dungeon
7 min read Grid DP Overview Grid DP problems involve a 2D grid where you make decisions at each cell and need to Read article
System Design
System Design Interview: Real-Time Analytics Dashboard (ClickHouse / Druid)
7 min read What Is Real-Time Analytics? Real-time analytics provides insights on data that is seconds to minutes old — not the hours Read article