This is beanstalkd, a fast, general-purpose work queue. See http://xph.us/software/beanstalkd/ for general info. To build beanstalkd, type "./configure" then "make". Requires libevent 1.4.1 or later. You can find libevent at http://www.monkey.org/~provos/libevent/. To install, copy the file "beanstalkd" anywhere you like.