Mapbox Web Performance Patterns

Solid performance guidance for Mapbox GL JS that actually prioritizes what matters. Starts with the big wins: killing initialization waterfalls by fetching data in parallel with map setup, keeping bundles lean by hosting styles externally instead of inlining them, and switching from thousands of HTML markers to GPU-accelerated symbol layers. The clustering patterns are especially practical, with clear thresholds for when to use what (HTML markers under 100, symbol layers up to 10K, clustering beyond that). These aren't micro-optimizations, they're the difference between a map that loads in a second versus three, and one that pans smoothly versus stuttering at 20 FPS.