Banjax is a library for low-level programming of IEEE 802.11 wireless network interfaces on the GNU/Linux operating system. The library is intended to simplify the writing of programs that sniff, manipulate and inject IEEE 802.11 traffic. Uses for banjax include traffic analysis, monitoring of link quality and capacity and performing acts of network evil such as deauthentication and man-in-the-middle attacks. Banjax is written in C++ and there is a SWIG wrapper to access banjax functionality from Guile.