System Design Interview: Design a Distributed Lock and Leader Election System
5 min read What Is a Distributed Lock? A distributed lock ensures that only one node in a cluster executes a critical section […] Read article
System Design
System Design
System Design Interview: Design a Loyalty and Rewards Points System
4 min read What Is a Loyalty and Rewards System? A loyalty program tracks user activity and awards points redeemable for discounts or Read article
System Design
System Design Interview: Design an Ad Click Aggregation System (Google/Meta Ads)
5 min read What Is an Ad Click Aggregation System? Ad platforms (Google Ads, Meta Ads, Amazon Advertising) must aggregate billions of ad Read article
Algorithms
Advanced Dynamic Programming Patterns: State Machine, Interval DP, Tree DP, Bitmask
6 min read Advanced Dynamic Programming Patterns Beyond the foundational DP patterns (Fibonacci, 0/1 knapsack, LCS), advanced interviews test state machine DP, interval Read article
System Design
System Design Interview: Design a Typeahead / Search Suggestion System
5 min read What Is a Typeahead / Search Suggestion System? A typeahead (also called autocomplete or search suggestion) system predicts what a Read article
Algorithms
String Algorithm Interview Patterns: Sliding Window, Palindromes, Anagrams, Rolling Hash
6 min read String Algorithm Patterns in Interviews String problems are ubiquitous in coding interviews. Most string challenges reduce to a small set Read article
System Design
System Design Interview: Design a Distributed Message Queue (SQS / RabbitMQ)
6 min read What Is a Distributed Message Queue? A message queue decouples producers (services that generate work) from consumers (services that process Read article
System Design
System Design Interview: Design a Live Sports Score System
6 min read What Is a Live Sports Score System? A live sports score system delivers real-time score updates to millions of concurrent Read article
System Design
System Design Interview: Design a Cloud File Storage System (Dropbox/Google Drive)
6 min read What Is a Cloud File Storage System? A cloud file storage system lets users upload, sync, and share files across Read article
System Design
System Design Interview: Design an Online Auction System (eBay)
5 min read What Is an Online Auction System? An online auction system allows sellers to list items and buyers to place competitive Read article
Algorithms
Union-Find (Disjoint Set Union) Interview Patterns: Connected Components, Kruskal’s MST
6 min read What Is Union-Find? Union-Find (Disjoint Set Union, DSU) is a data structure that tracks a collection of elements partitioned into Read article
System Design
System Design Interview: Design a Web Crawler and Search Indexer
5 min read What Is a Web Crawler and Search Indexer? A web crawler systematically downloads web pages. A search indexer processes those Read article
System Design
System Design Interview: Design a Multi-Region Database System
6 min read Why Multi-Region Databases? A single-region database has two critical weaknesses: latency (users in Europe querying a US database experience 150ms+ Read article
Algorithms
Greedy Algorithm Interview Patterns: Intervals, Jump Game, Task Scheduler
6 min read What Are Greedy Algorithms? A greedy algorithm makes the locally optimal choice at each step, never backtracking, hoping that local Read article
System Design
System Design Interview: Design a Streaming Data Pipeline (Kafka + Flink)
6 min read What Is a Streaming Data Pipeline? A streaming data pipeline continuously ingests, processes, and routes events in real time — Read article