2026.01.10S·14Notification System Design: Sending Alerts to Millions of Users
Sending one notification is easy. As notifications scale up, preventing duplicates, respecting preferences, and handling retries becomes a completely different engineering problem.
System DesignNotificationArchitecture
→2026.01.07S·11News Feed System Design: Push vs Pull and the Fan-out Problem
Building a feed like Instagram sounds simple until a user with 1M followers posts. Understanding push vs pull models and fan-out strategies.
System DesignFeedArchitecture
→2026.01.05S·09Designing a URL Shortener: Looks Simple, Full of Traps
A URL shortener sounds trivial until you face hash collisions, expiration policies, and redirect latency. A microcosm of system design.
System DesignArchitectureHashing
→2025.07.08F·159Replication: Availability and Read Distribution
Understanding high availability and read performance improvement through database replication
databasereplicationhigh-availability
→2025.07.07F·158Sharding: Horizontal Partitioning
Understanding database sharding and handling massive traffic through practical experience
databaseshardingscalability
→2025.06.10S·06Database Sharding: How to Scale Beyond Limits
When Scale-Up fails, Scale-Out is the answer. Vertical vs Horizontal Partitioning, Shard Key selection strategies (Geo vs Hash), and the complexity of Distributed Transactions.
System DesignDatabaseBackend
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