**OpenSnitch** is a GNU/Linux port of the Little Snitch application firewall. ### Daemon The `daemon` is implemented in Go and needs to run as root in order to interact with the Netfilter packet queue, edit iptables rules and so on, in order to compile it you will need to install the `libpcap-dev` and `libnetfilter-queue-dev` libraries on your system, then just: cd daemon go build . ### Qt5 UI The user interface is a python script running as a `gRPC` server on a unix socket, to order to install its dependencies: cd ui pip install -r requirements.txt ### Running First, you need to decide in which folder opensnitch rules will be saved, it is suggested that you just: mkdir -p ~/.opensnitch/rules Now run the daemon: sudo /path/to/daemon -ui-socket-path /tmp/osui.sock -rules-path ~/.opensnitch/rules And the UI service as your user: python /path/to/ui/main.py --socket /tmp/osui.sock ### FAQ ##### Why Qt and not GTK? I tried, but for very fast updates it failed bad on my configuration (failed bad = SIGSEGV), moreover I find Qt5 layout system superior and easier to use. ##### Why gRPC and not DBUS? At some point the UI service will also be able to use a TCP listener, at that point the UI itself can be executed on any operating system, while receiving messages from a single local daemon instance or multiple instances from remote computers in the network, therefore DBUS would have made the protocol and logic uselessly GNU/Linux specific.