lldcoding.comDesign (LLD) Rate Limiter - C++📌 1. Functional Requirements A Rate Limiter system should: Limit requests per client/user Support multiple rate limiting algorithms Allow dynamic algorithm switching Support different limits per 6d ago·13 min read
lldcoding.comDesign (LLD) Vending Machine - C++1️⃣ Functional Requirements A vending machine should support: Add products Add inventory (quantity) Insert money (multiple denominations) Select product Dispense product Return change Cancel trFeb 28·7 min read
lldcoding.comDesign (LLD) Hotel Management System - C++1️⃣ Functional Requirements A hotel system should support: Add hotel rooms Search rooms (by type, price, availability) Book room Cancel booking Check-in Check-out Generate bill Payment processFeb 26·8 min read
lldcoding.comDesigning a Like / Reaction System (Facebook / LinkedIn) - Database ModellingModern platforms (Reddit, LinkedIn, YouTube) support multiple reaction types per entity. Core Requirements ✅ One user → one reaction per entity ✅ Reaction can change over time ✅ Extremely write-heavy ✅ Reads need fast aggregated counts ✅ Prevent...Jan 19·4 min read
lldcoding.com📘 Why Indexes Are Not FreeThe Silent Cost Behind Fast Reads Indexes don’t make systems faster —they shift cost from reads to writes, memory, and latency tails. 🧠 The Illusion CREATE INDEX idx_user_email ON users(email); Looks harmless.But this single line changes your ent...Jan 18·3 min read