1. Overview A distributed job scheduler is a system that reliably executes tasks (jobs) at specified times or intervals across a cluster of machines. It powers background processing in virtually every large-scale application: cron jobs, ETL pipelines, report generation, cache…

1. Overview A distributed rate limiter is a critical infrastructure component that enforces per-entity request quotas across a fleet of stateless application servers (e.g., microservices behind a load balancer). In a single-node system, rate limiting is trivial (in-memory counter), but…

1. Overview This case study presents a comprehensive design for a fully distributed, highly available, and linearly scalable key-value store, directly modeled after Amazon’s Dynamo technology (the foundational system behind DynamoDB, Riak, Cassandra, and Voldemort). The core philosophy is radical…

1. Overview This case study outlines a scalable, distributed web crawler architecture capable of processing billions of pages daily. It incorporates fault tolerance, politeness policies, and deduplication. The implementation leverages .NET 8 for high performance, with components for orchestration, fetching,…

1. Functional Requirements 2. Non-Functional Requirements 3. Estimation (Back-of-the-envelope) 4. High-Level Architecture Key Insight: 99%+ of traffic is GET /:shortCode → 301 redirect → Optimize the redirect path aggressively. 5. Core Design Decisions 5.1 Short Code Generation Strategy Option Chosen:…

In the domain of e-commerce transaction processing, a reliable workload is characterized by its ability to consistently fulfill predefined reliability objectives, such as ensuring seamless order placement, payment authorization, and inventory updates without interruption. This reliability is achieved through proactive…