The core distinction between a High-Level Plan (HLD) and a Detailed Architecture (LLD) lies in their scope . An HLD provides a broader picture of the system , outlining the key components and their relationships – it's essentially the "what" and "why." Conversely, an LLD goes into the granular pa

Caching Strategies Start With One Question: How Stale Can This Data Be? Most caching answers jump straight to Redis. The stronger answer starts one step earlier. Caching is a deliberate trade of freshness for speed, so the first thing to establish is how much staleness t