rf write large geotiff(bigtiff) / cog

I have two questions while using rasterframes:
1. When using rf to write geotiff, if the image is large(>4G), the error oom is reported. If I want to write a bigtiff, is there any solution?
2. rf provides full support for reading cog, but it seems that it does not provide a way to write cog (or maybe I missed it) Does rf provide a method to write cog like GeoTrellis?