Spring Cleaning 2026 Day 3: h3 & fixing ascii boxes

H3 and Fixing ASCII Boxes Smaller updates today. H3 https://github.com/mattsta/h3 H3 has been either mostly complete, closed, or abandoned for a while, but there’s still room for improvement. I’m forking it here with my own refactors and improvements: https://github.com/mattsta/h3 Performance — the headline numbers Single-cell hot path API upstream → optimized speedup cellToBoundary 0.50 µs → 0.23 µs ~2.13× cellToLatLng 0.12 µs → 0.08 µs ~1.55× cellToVertexes (full ring) 19.5 µs → 15.1 µs ~1.29× polygonToCellsExperimental (Full) varies ~1.65–1.76× polygonToCellsExperimental (Overlapping) varies ~1.32–1.49× polygonToCellsExperimental (Center) varies ~1.39–1.46× polygonToCells (legacy polyfill) varies ~1.13–1.18× gridDisk (k=10–40) varies ~1.17–1.22× gridDisk pentagon paths (k=10–40) varies ~1.51–1.84× Bulk cellToChildren (allCellsAtRes) varies ~1.84–2.15× New bulk APIs (cellsToLatLngs, on top of single-cell wins) For applications converting millions of cells (visualization, map…