The fundamental separation between a Architectural Design (HLD) and a Low-Level Plan (LLD) lies in their focus. An HLD provides a general overview of the system , outlining the major modules and their interactions – it's essentially the "what" and "why." Conversely, an LLD goes into the specific det
Caching Strategies Explained: Patterns, TTLs, Pitfalls (2026)
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 the product can tolerate. A pr