System Design

⏱ 6 min read What Is a Digest Email Service? A Digest Email Service batches individual notification events that would otherwise generate separate emails […] Read article

⏱ 4 min read What Is a Geospatial Index Service? A Geospatial Index Service stores, indexes, and queries geographic coordinates at scale. It powers Read article

⏱ 4 min read What Is an Identity Service? An Identity Service handles authentication and authorization: it answers the questions “who are you?” (authn) Read article

⏱ 4 min read What Is a Distributed Lock Service? A distributed lock service allows multiple processes or nodes across a network to coordinate Read article

⏱ 5 min read What Is a Distributed Semaphore? A distributed semaphore limits the number of concurrent processes that can access a shared resource Read article

⏱ 4 min read What Is a Metrics Aggregation Service? A metrics aggregation service collects raw telemetry data (counters, gauges, histograms) emitted by application Read article

⏱ 5 min read What Is an On-Call Management Service? An on-call management service determines which engineer is responsible for responding to an alert Read article

⏱ 4 min read What Is a Social Graph Service? A social graph service models relationships between users on a platform. These relationships can Read article

⏱ 4 min read What Is Write-Through Cache? Write-through caching is a strategy where every write to the cache is synchronously propagated to the Read article

⏱ 4 min read What Is an ETL Service? Extract, Transform, Load (ETL) is the classic pattern for moving data from operational systems into Read article

⏱ 5 min read What Is a Billing System? A billing system manages the full revenue lifecycle: creating subscription plans, tracking usage, generating invoices, Read article

⏱ 5 min read What Is Content-Based Filtering? Content-based filtering recommends items similar to those a user has already engaged with, based on the Read article

⏱ 5 min read What Is a Thumbnail Generator Service? A thumbnail generator service automatically produces small preview images from source assets — videos, Read article

⏱ 4 min read What Is an Image Processing Service? An image processing service accepts raw image uploads, applies a configurable set of transformations Read article

⏱ 5 min read What Is a Content Delivery Network? A Content Delivery Network (CDN) is a geographically distributed system of proxy servers and Read article