A Dropbox-like file manager that let you manage your data anywhere it is located:
FTP • FTPS • SFTP • WebDAV • Git • S3 • LDAP • Mysql
CardDAV • CalDAV • Backblaze B2 • Minio
Dropbox • Google Drive

Filestash started as an attempt to solve the Dropbox problem by abstracting the storage aspect so you can "bring your own backend" by implementing this interface:

type IBackend interface {
	Init(params map[string]string, app *App) (IBackend, error) // constructor
	Ls(path string) ([]os.FileInfo, error)           // list files in a folder
	Cat(path string) (io.ReadCloser, error)          // download a file
	Mkdir(path string) error                         // create a folder
	Rm(path string) error                            // remove something
	Mv(from string, to string) error                 // rename something
	Save(path string, file io.Reader) error          // save a file
	Touch(path string) error                         // create a file
	LoginForm() Form                                 // dynamic form generation for the login
}

It has evolved with plugins which are the lego bricks you can assemble together to form a solution that works for you. You can bring your own identity provider, your own authorisation, your own search and more. If there's something you want, plugin will likely make it possible.

Some outside the box example of this "filesystem as a framework" ideas we've done for the sake of science: