These alternative recommendations are exactly what I'm looking for when browsing the comments.
Two scripts linked at the bottom of README.md are almost perfect and I used one or another for years, but one of them sometimes misses to hard link with previous backup, creating new full backup and wasting resources -- not something that's easy to detect since they all look correct before 'du' or similar analysis.
saf solves few of the problems I faced during the years in a elegant way: multiple targets, target related commands, reliability. Why not XY? Why not saf?