⏱ 3 min read Data Model Closure table for efficient subtree queries: ThreadAncestor ( ancestor_id BIGINT, descendant_id BIGINT, depth INT, PRIMARY KEY (ancestor_id, descendant_id) […] Read article

⏱ 3 min read PoP Selection and GeoDNS When a client issues a DNS query, GeoDNS maps the client IP to a geographic region Read article

⏱ 4 min read ETA Calculator Service: Low Level Design Road Network Graph Schema Node (Intersection) ——————- id BIGINT PK lat DOUBLE PRECISION lng Read article

⏱ 3 min read Location Sharing Service: Low Level Design Data Model Location Table (Time-Series) Location ——– device_id BIGINT lat DOUBLE PRECISION lng DOUBLE Read article

⏱ 4 min read Geo-Fencing Service: Low Level Design Data Model GeoFence Table GeoFence ——– id BIGINT PK name VARCHAR(255) type ENUM(‘circle’,’polygon’) center_lat DOUBLE Read article

⏱ 6 min read Overview An SSH key rotation service automates generation of new keypairs, distribution to all target hosts, a grace period with Read article

⏱ 5 min read Overview A secrets manager provides secure storage, access control, and lifecycle management for credentials, API keys, and other sensitive values. Read article

⏱ 5 min read Saga Orchestrator: Low Level Design The Saga pattern manages distributed transactions across microservices. An orchestrator-based saga drives each step sequentially Read article

⏱ 4 min read CQRS Service: Low Level Design CQRS (Command Query Responsibility Segregation) separates the write model (commands) from the read model (queries), Read article

⏱ 7 min read Overview A schema registry is a centralized store for event and message schemas used in event-driven architectures. Producers register schemas Read article

⏱ 10 min read A metrics pipeline collects numeric time-series data from every service and infrastructure component, aggregates it efficiently, stores it compactly, and Read article

⏱ 6 min read What Is a Configuration Push Service? A configuration push service stores application configuration, propagates changes to all connected clients in Read article

⏱ 5 min read What Is a Feature Toggle Service? A feature toggle service stores toggle definitions, evaluates them against a user and request Read article

⏱ 5 min read What Is an A/B Test Assignment Service? An A/B test assignment service deterministically buckets users into experiment variants, maintains consistent Read article

⏱ 5 min read What Is a Progress Tracker Service? A progress tracker service ingests completion events from multiple upstream services, detects when users Read article