System Design

⏱ 5 min read What an Access Log Service Provides Every HTTP request to a web service generates a log record. At scale, this […] Read article

⏱ 5 min read What a Session Store Does A session store maintains server-side state for authenticated users across stateless HTTP requests. The client Read article

⏱ 5 min read Why PII Scrubbing Is Hard PII (Personally Identifiable Information) appears in many forms: structured fields like email addresses and SSNs, Read article

⏱ 5 min read What a Consensus Log Provides A consensus log is a fault-tolerant, ordered sequence of records that all nodes in a Read article

⏱ 5 min read What an Orchestrator Does A data pipeline orchestrator schedules and executes directed acyclic graphs (DAGs) of computational tasks. Each DAG Read article

⏱ 5 min read What a Request Router Does A request router sits between clients and backend services, inspecting each incoming HTTP request and Read article

⏱ 4 min read What a Response Cache Does A response cache sits in front of upstream services and stores HTTP responses so that Read article

⏱ 4 min read The Distributed Scheduler Problem A scheduler that runs on a single node is a single point of failure. A scheduler Read article

⏱ 5 min read Coupon Schema A coupon service manages promotional codes that apply discounts to orders. The core schema: CREATE TABLE coupons ( Read article

⏱ 5 min read Promotion Schema A discount engine evaluates active promotions against a cart and computes the final discounted price. The promotion schema Read article

⏱ 6 min read Dependency Graph Construction An asset pipeline must understand the relationships between source files to build correctly. The dependency graph is Read article

⏱ 5 min read Core Schema The subscription manager tracks the relationship between users, plans, and billing periods. CREATE TABLE subscriptions ( subscription_id UUID Read article

⏱ 5 min read URL Scheme An image optimization service accepts transform parameters via URL and returns a processed image. A clean URL scheme Read article

⏱ 5 min read Preference Hierarchy A user preferences service must resolve the right value for any preference key given a user and device Read article

⏱ 5 min read Ingestion Flow A webhook ingestion service receives HTTP POST requests from third-party providers (Stripe, GitHub, Twilio) and delivers the events Read article