#music #audio #tagging #mp3 #organiser

app mack

An opinionated, fast music organiser

7 releases (2 stable)

Uses old Rust 2015

new 1.0.1 May 7, 2021
1.0.0 May 18, 2020
0.3.0 Oct 25, 2019
0.2.2 Oct 25, 2019
0.1.0 Sep 6, 2018

#37 in Audio

41 downloads per month


570 lines


mack is to music files as black is to code formatting. It enforces standards around both consistency of the metadata (eg. ID3 version) and the metadata itself (eg. "feat" tagging).

Examples of fixes

  • Moving featured artists from the artist tag to the title
  • Enforcing a consistent "feat" format in title tags
  • Whitespace normalisation
  • Renaming files to format "{artist}/{album}/{track} {title}"


mack [DIR]

You can also see what would be changed first using --dry-run.


You need TagLib installed on your system to build. This can be found in the following packages:

After that, cargo build as normal.


mack has a strong focus on performance. Files which were not updated since the last mack run will not be examined at all. On a sample modern laptop with a mid-spec SSD, this means that we only take 0.02 seconds to run over 5000 files under most circumstances (0.2 seconds on the very first run).


In a similar philosophy to black, most things cannot be configured -- you either use mack or you don't. There is one thing you can control though: if you don't want a particular file to be touched by mack, add _NO_MACK as a substring anywhere in the comment tag.


~54K SLoC