grandperspective

Install command: 
brew install --cask grandperspective

Name: GrandPerspective

Graphically shows disk usage within a file system

https://grandperspectiv.sourceforge.net/

Cask JSON API: /api/cask/grandperspective.json

Cask code: grandperspective.rb on GitHub

Current version: 3.6

Requirements: macOS >= 10.11

Versions:

Intel catalina 3.3
mojave 3.3
high sierra 3.0.1
sierra 3.0.1
el capitan 3.0.1

Analytics:

Installs (30 days)
grandperspective 772
Installs (90 days)
grandperspective 2,286
Installs (365 days)
grandperspective 7,354