System Design

⏱ 8 min read Core Requirements A file sharing platform allows users to upload, organize, and share files and folders. Key features: file upload/download, […] Read article

⏱ 7 min read Requirements and Scope An appointment scheduling system allows users (customers) to book time slots with service providers (doctors, barbers, consultants). Read article

⏱ 7 min read Core Entities Restaurant: restaurant_id, name, address, lat, lng, cuisine_type, rating, prep_time_minutes (avg), is_active, operating_hours. MenuItem: item_id, restaurant_id, name, description, price, Read article

⏱ 6 min read Requirements A live comments system allows users to post comments on content (articles, videos, livestreams) and see other users’ comments Read article

⏱ 7 min read Core Entities Company: company_id, name, description, logo_url, website, size, industry, verified (boolean). Job: job_id, company_id, title, description, location, is_remote, employment_type Read article

⏱ 7 min read What is a Workflow Engine? A workflow engine executes multi-step processes where steps have dependencies, can run in parallel, and Read article

⏱ 5 min read Core Entities Contact: contact_id, first_name, last_name, email (unique), phone, company_id, job_title, source (INBOUND, OUTBOUND, REFERRAL), owner_id (assigned sales rep), created_at, Read article

⏱ 7 min read Core Responsibilities An identity service (also called an IAM or auth service) handles: Authentication (who are you?) — verifying credentials Read article

⏱ 7 min read Core Entities PaymentIntent: intent_id (UUID), merchant_id, customer_id, amount (integer cents), currency, status (CREATED, PROCESSING, REQUIRES_ACTION, SUCCEEDED, FAILED, CANCELLED, REFUNDED), payment_method_id, Read article

⏱ 7 min read Core Architecture A search system takes a text query and returns a ranked list of documents (web pages, products, articles). Read article

⏱ 7 min read Core Entities User: user_id, email, timezone, working_hours (JSON: {mon: “9:00-17:00”, …}). Calendar: calendar_id, user_id, name, color, is_primary, visibility (PRIVATE, PUBLIC, Read article

⏱ 7 min read What is a Document Store? A document store (MongoDB, DynamoDB, Couchbase, Firestore) stores JSON-like documents with flexible schemas — each Read article

⏱ 7 min read Core Requirements A collaborative document editor allows multiple users to edit the same document simultaneously, with changes reflected in near-real-time Read article

⏱ 7 min read Requirements and Scale An analytics pipeline collects events from product surfaces (web, mobile, backend services), processes them in real time Read article

⏱ 7 min read Core Entities Event: event_id, name, venue_id, event_date, doors_open, start_time, status (ON_SALE, SOLD_OUT, CANCELLED, COMPLETED), total_capacity. Venue: venue_id, name, address, seating_map_url, Read article