Thanks for the feedback! We've recently implemented some pretty big performance improvements in the filesystem, including prefetching files, caching them encrypted to your local disk, and journaling for writes (allowing us to sync them over some period rather than blocking on your network connection). If you're still experiencing poor performance in the filesystem, please file a ticket on github.com/keybase/kbfs or contact me on Keybase chat (keybase.io/jzila).