Author name: techinterview.org

⏱ 5 min read Upload Flow When a client uploads an image, the request hits an API gateway that performs initial validation: file size […] Read article

⏱ 5 min read A metrics collection service captures numeric measurements over time, stores them efficiently, and powers alerting and dashboards. This post covers Read article

⏱ 4 min read Streaming Analytics Service: Low Level Design A streaming analytics service ingests high-velocity event data, applies stateful computations in real time, Read article

⏱ 6 min read What Are Read Receipts? Read receipts tell message senders whether their messages have been delivered and read. The feature is Read article

⏱ 5 min read A news feed service delivers a ranked, personalized stream of posts to each user. The central design question is delivery Read article

⏱ 6 min read A payment dispute resolution service manages the lifecycle from the moment a customer contests a charge through investigation, bank communication, Read article

⏱ 4 min read Overview A calendar and meeting invite service lets users create events, invite attendees, track RSVPs, and synchronize with external calendar Read article

⏱ 5 min read A password manager is security-critical software. Every design decision either exposes user secrets or protects them. The central architectural constraint Read article

⏱ 6 min read The transactional outbox pattern solves one of the most common reliability problems in microservices: how to write to a database Read article

⏱ 7 min read Overview A data anonymization service transforms raw datasets containing personally identifiable information (PII) into privacy-safe versions that can be used Read article

⏱ 6 min read What Is a Distributed Caching Layer? A distributed caching layer sits between your application and its primary data store, serving Read article

⏱ 6 min read A dynamic pricing engine adjusts prices in real time based on demand signals, inventory, and business rules. The design must Read article

⏱ 5 min read A matchmaking service pairs players into balanced, low-latency game sessions. The design touches skill rating systems, queue management, match formation Read article

⏱ 6 min read A session replay service records a user’s browser interactions and reconstructs them for playback — enabling UX debugging, funnel analysis, Read article

⏱ 6 min read A thumbnail generation service converts uploaded images into resized, optimized variants for display at different sizes across web and mobile Read article