xquartz

Install command: 
brew install --cask xquartz

Name: XQuartz

Open-source version of the X.Org X Window System

https://www.xquartz.org/

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

Cask code: xquartz.rb on GitHub

Current version: 2.8.5

Requirements: macOS >= 10.11

Analytics:

Installs (30 days)
xquartz 8,521
Installs (90 days)
xquartz 24,777
Installs (365 days)
xquartz 104,631