This is neat! I am quite a fan of all the go based file systems that are springing up. Question: what are the main compare and contrast points between juice and seaweed fs? Here is a compendium for those interested: https://github.com/gostor/awesome-go-storage
The core of seaweedfs is to manage many small blobs, you can use SeaweedFS together with JuiceFS to have a full featured POSIX file system.