Firejail is a SUID program that reduces the risk of security breaches by restricting the running environment of untrusted applications using Linux namespaces and seccomp-bpf. It allows a process and all its descendants to have their own private view of the globally shared kernel resources, such as the network stack, process table, mount table.

Written in C with virtually no dependencies, the software runs on any Linux computer with a 3.x kernel version or newer. The sandbox is lightweight, the overhead is low. There are no complicated configuration files to edit, no socket connections open, no daemons running in the background. All security features are implemented directly in Linux kernel and available on any Linux computer. The program is released under GPL v2 license.

Firejail can sandbox any type of processes: servers, graphical applications, and even user login sessions. The software includes security profiles for a large number of Linux programs: Mozilla Firefox, Chromium, VLC, Transmission etc. To start the sandbox, prefix your command with `firejail`:

```bash

$ firejail firefox # starting Mozilla Firefox

$ firejail transmission-gtk # starting Transmission BitTorrent

$ firejail vlc # starting VideoLAN Client

$ sudo firejail /etc/init.d/nginx start # starting nginx web server

```

To protect user’s privacy, we deploy a very strict Mandatory Access Control (MAC) on top of the existing file system. Access to passwords, encryption keys, and private data is blocked for more than 1000 different desktop applications. As a general rule, networked apps and games have access only to configuration files and Downloads directory.

Firejail is a community project. We are not affiliated with any company, and we don’t have any commercial goals. Our focus is the Linux desktop. Home users and Linux beginners are our target market. The software is built by a large international team of volunteers on GitHub.