Uhhh ... where did the comparison between overlaying fses and FUSE come from? Overlaying of filesystems is for completely different purposes. It&#x27;s not even suitable for Dropbox&#x27;s Project Infinite — what would it be overlayed upon? How would dropboxd send&#x2F;receive file info&#x2F;data to&#x2F;from the overlaying fs&#x27;s driver?<p>The mere use of FUSE doesn&#x27;t make an fs complicated or things &quot;severe&quot;. It&#x27;s just a really simple API made available to userspace processes. In fact, you can build an fs in FUSE that does overlaying itself, using multiple, isolated processes. Or you can use a single, simple, small process to implement a simple fs. FUSE is literally just the glue that would allow something like dropboxd to send&#x2F;recieve file info&#x2F;data to&#x2F;from the VFS.