fclones is a command line utility that identifies groups of identical files
and gets rid of the file copies you no longer need. It comes with plenty of
configuration options for controlling the search scope and offers many ways
of removing duplicates. For maximum flexibility, it integrates well with other
Unix utilities like `find` and it speaks JSON, so you have a lot of control
over the search and cleanup process.

fclones treats your data seriously. You can inspect and modify the list of
duplicate files before removing them.
There is also a `--dry-run` option that can tell you exactly what changes on
the file system would be made.

fclones has been implemented in Rust with a strong focus on high performance
on modern hardware.
It employs several optimization techniques not present in many other programs.
It adapts to the type of the hard drive, orders file operations by physical
data placement on HDDs, scans directory tree in parallel and uses prefix
compression of paths to reduce memory consumption when working with millions of
files. It is also friendly to page-cache and does not push out your data out of
cache.

As a result, fclones easily outperforms many other popular duplicate finders by
a wide margin on either SSD or HDD storage.