Spell Checker System: Overview A spell checker takes an input word (potentially misspelled) and returns a ranked list of correction […]
Typeahead Autocomplete System: Overview A typeahead (autocomplete) system returns ranked query completions as the user types, with latency under 50ms
Proximity Search System: Overview A proximity search system finds entities (restaurants, drivers, users) within a geographic radius of a query
Graph Search System: Overview A graph search system enables queries over a network of nodes and edges — users, connections,
Recommendation Feedback Loop: Overview A recommendation system without a feedback loop becomes stale. The feedback loop closes the cycle: collect
User Activity Feed: Overview A user activity feed aggregates events from actors a user follows and surfaces them in reverse-chronological
Why a Dedicated Experiment Platform? A/B testing sounds simple — split users, measure a metric, run a t-test — but
Why Model Serving Is Not Trivial Deploying a model to production is an engineering discipline separate from training one. A
What Is an ML Feature Store? An ML feature store is a centralized system for computing, storing, versioning, and serving
Streaming ETL Pipeline Low-Level Design A streaming ETL pipeline continuously consumes events from a message broker, transforms them in real
Data Lake Architecture Low-Level Design A data lake is a centralized repository that stores structured and unstructured data at any
Database Schema Migration System Low-Level Design A schema migration system manages the evolution of a database schema alongside application code.
Query Optimizer Low-Level Design A query optimizer transforms a parsed SQL query into an efficient execution plan. The optimizer evaluates
Database Connection Pool Low-Level Design A database connection pool maintains a set of pre-established connections to a database server, lending
Load Balancer Low-Level Design A load balancer distributes incoming network traffic across a pool of upstream servers, ensuring no single
