From the Arch Linux wiki:
Anything-sync-daemon(asd) is a tiny shell script designed to manage target directories in tmpfs and to periodically sync them back to your physical disc (HDD/SSD). This is accomplished via a symlinking step and an innovative use of rsync to maintain back-up and synchronization between the two. One of the major design goals of asd is a completely transparent user experience.
What would it take to use this in Ubuntu?
11 Answer
It would take an upstart /etc/init conf script. The upstream repository now includes an Upstart init script designed specifically for Ubuntu.
goanysync is a program with similar
functionality to asd and includes upstart init script and a pre-build deb
package for testing. Packaging it properly for Ubuntu should be quite easy.
Also just taking goanysyncs upstart conf file and using it with slight modification for asd should work.
