Bartlby is a network and system monitor, completely written in C, to provide a scalable framework with the ability to monitor networks of various sizes. It consists of a core daemon, several plugins, and a Web GUI (PHP extension). The core daemon checks (over active/passive TCP) services/hosts and notifies users in case of critical service conditions (mail, SMS, ICQ, and custom triggers are supported). Bartlby provides an open plugin interface to give every administrator an easy to use option to extend the plugin base, and a fully customizable GUI (written in PHP using a C extension). Nearby everything can be controlled via an XML interface.