LuLu

LuLu is an open-source, lightweight firewall for macOS that monitors and controls outgoing network traffic. It alerts users to unexpected app connections, blocking unauthorized data leaks. Developed by Objective-See, it balances simplicity with granular control—ideal for casual users and security fans alike. Unlike macOS’s built-in firewall, LuLu offers real-time notifications and app-specific access rules, keeping you in charge of your data. It supports latest macOS versions, integrates smoothly with system security features, and has a minimal interface that avoids overwhelming users while letting power users customize rules further.