Today I talked with Matz("the" ruby language designer) in XP Fiesta 2006 Kansai and discussed for a few minutes commonality of Ruby and Agile. Both of us were invited yesterday as speakers of the fiesta.

Ruby is categorized as a light weight language, dynamic language or "P language(with long tail)". Agile software development approaches are also formerly called "Light Weight Methodologies", and changed its umbrella name to "Agile" so to directly express positive properties. Then why not call Ruby an "Agile Language?"

Matz pointed me to a Kikaineko's entry.
http://d.hatena.ne.jp/kikaineko/20060903

It's in Japanese, so I'm translating the points he made very briefly.

Agile software development values;
Individuals and interactions over processes and tools
Working software over comprehensive documentation
Customer collaboration over contract negotiation
Responding to change over following a plan

These four values can be translated as follows from the language viewppoint.

Languages should be human-oriented, human-friendly.
Languages should guide programmers to readable code
(as a substitution of document)
Language specification should be consistent and hospitable.
(collaboration of programmers and a language over contract between them)
Languages should embrace change.

He is a ruby programmer as well as a developer of Kikaineko-Mocker, a TDD tool which generates mock objects from tests.

Maz and I agreed that programming and software development are both "human activities" which affects each other. Agile and Ruby both value "having fun" in the activity as a Life-hack!

As I mentioned in the last entry, I've been catching a strong "social" commonality of agile and ruby communities in Japan.
http://jude-users.com/en/modules/weblog/details.php?blog_id=17

How about in the other area of the world ? Pragmatic Programmers likes Ruby a lot, and the pragmatic bookshelf series have good Ruby books, too.

After the Fiesta, I went for another drink with several rubists.

P.S.
Here's a wonderful XP Fiesta theme song, "Dear XP" and the movie!
http://www.youtube.com/watch?v=zpw8h4OGNxg