Dang, fun memories of when I was first getting in to geo/data stuff and doing a lot of web mapping stuff with D3, Leaflet and friends. Seems as tools like Vector tiles/PMTiles have supplanted topojson for a lot of visualization oriented use cases.

I'm gonna have to dive into a rabbit-hole! I was working on an ESRI Shapefile to GeoJson converter back in those days. But D3 and Leaflet were such cool tech! MapBox too. Linking SagaGIS with PostGIS to do pre/post wildfire analysis was my jam.