filemon

Install command: 
brew install --cask filemon

Name: File Monitor

FSEvents client

https://newosxbook.com/tools/filemon.html

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

Cask code: filemon.rb on GitHub

Current version: 2.0

Requirements: macOS >= 10.11

Analytics:

Installs (30 days)
filemon 6
Installs (90 days)
filemon 14
Installs (365 days)
filemon 76