https://github.com/objective-see/LuLu

LuLu is the free open-source macOS firewall that aims to block unauthorized (outgoing) network traffic

LuLu

⚠  please note:

LuLu is currently in alpha. 

This means it is currently under active development and still contains known bugs. 
As such, installing it on any production systems is not recommended at this time! 

Also, as with any security tool, proactive attempts to specifically bypass LuLu's protections will likely succeed. 
By design, LuLu (currently) implements only limited 'self-defense' mechanisms.

LuLu is the free open-source macOS firewall that aims to block unauthorized (outgoing) network traffic, unless explicitly approved by the user:

Full details and usage instructions can be found here.

To Build
LuLu should build cleanly in Xcode (though you will have to remove code signing constraints, or replace with your own Apple developer/kernel code signing certificate).

To Install
For now, LuLu must be installed via the command-line. Build LuLu or download the pre-built binaries/components from the Releases page, then execute the configuration script (configure.sh) with the -install flag, as root:

//install
$ sudo configure.sh -install

❤  Love this product or want to support it? Check out my patreon page :)

Mahalo!
This product is supported by the following patrons:

• Lance Gaines
• Ash Morgan
• Khalil Sehnaoui
• Nando Mendonca
• Bill Smartt
• Martin OConnell
• David Sulpy
• Shain Singh
• Chad Collins
• Harry Hoffman
• Keelian Wardle
• Christopher Giffard
• Conrad Rushing
• soreq
• Stuart Ashenbrenner
• trifero
• Peter Sinclair
• Ming
• Gamer Bot