One of the most common mistakes engineers make is choosing a database based on hype instead of access patterns. The truth is: 🟢 Most web applications should start with PostgreSQL. It’s flexible enough for transactions, analytics, JSON documents, search, and scaling. Then add specialized databases only when you actually need them. Quick cheat sheet: 📦 PostgreSQL → SaaS, marketplaces, internal tools, fintech, most startups 🍃 MongoDB → Flexible schemas, content platforms, rapidly evolving products ⚡ Redis → Caching, sessions, rate limiting, leaderboards 📈 TimescaleDB → Metrics, logs, IoT, observability, time-series workloads 🔥 Firebase → Mobile apps, MVPs, real-time collaboration 🔍 Elasticsearch → Search 🕸️ Neo4j → Relationships and graph data The best architecture isn’t the most complicated one. It’s the simplest one that solves today’s problem while leaving room for tomorrow. What database are you choosing for your next project? @hackproduct #Database #PostgreSQL #MongoDB #Redis #SystemDesign - @hackproduct9