retwill is a fork of the acclaimed but apparently abandoned language twill.
twill is a simple scripting language intended for programmatic or automated browsing of Web sites.
Documentation is available in the release package under doc/index.txt or doc/index.html.
The latest release as well as all documentation is always online at http://twill.idyll.org/. You can also find information on mailing lists, bug fixes, and new releases there.
twill is Copyright (C) 2005, 2006, 2007 by C. Titus Brown, and is available for use, modification, and distribution under the MIT license.
retwill, for its turn, includes some new functionalities, such as XPath-supporting "find" command and use of non-string values in dollar expressions (e.g. "${1}"), along with some improvements, such as the use of most recent versions of mechanize.