a future project for some day

[Skaperen]

it has no option to hardlink duplicates though it does have an option to delete duplicates

You could use it as an external command to locate the duplicates, it is quite fast.

i still am inclined to make my own. i can boost the speed by doing only a partial checksum to begin with. the vast majority of files that are not identical have some difference very early on. also, i have had cases where i did not want to consider files to be identical (for hardlinking) unless they also have identical timestamps (i had this option on my C version).

if the first N bytes are not the same, no further checksumming is needed unless another file of the same size has the first N bytes the same (in which case i increase N and retry).

have you ever used fdupes? i'm playing around with it right now on a cloud instance that has a backup copy of my music collection, which has a lot of duplicate paths.