Fusil is a Python library used to write fuzzing programs. It helps to start process with a prepared environment (limit memory, environment variables, redirect stdout, etc.), start network client or server, and create mangled files. Fusil has many probes to detect program crash: watch process exit code, watch process stdout and syslog for text patterns (eg. "segmentation fault"), watch session duration, watch cpu usage (process and system load), etc.
Fusil is based on a multi-agent system architecture. It computes a session score used to guess fuzzing parameters like number of injected errors to input files.
Available fuzzing projects: ClamAV, Firefox (contains an HTTP server), gettext, gstreamer, identify, libc_env, libc_printf, libexif, linux_syscall, mplayer, php, poppler, vim, xterm.