I’m still perplexed how cryptic the docs are. No info on return types. Also this example crashed with MethodError, couldn’t find how to call it on a vector.
cities2 = GDF.read("/tmp/cities.geojson")
sc = AG.importEPSG(4326)
tc = AG.importEPSG(3857)
AG.createcoordtrans(sc, tc) do transform
AG.transform!.(cities2.geometry, transform)
end