In the newly formed Rails community, the word 'enterprise' is becoming a dirty word. For many people the Rails framework, with its aggressive simplicity, is the antithesis of over-complex 'enterprisey' frameworks.
At the recent RailsConf, PragDave's opening keynote highlighted a bunch of unsolved issues with Rails, several of which involved dealing with some of these enterprisey concerns. An example of this was his call for support of more varied database structures, such as having compound primary keys.
DHH's response to this could not have been a more emphatic refusal. With a clever visual manipulation of his recent wired cover, DHH projected himself as the Neo of the software world, forcefully proclaiming himself to be in a better place, and telling the enterprise world that they need to join him, not the other way around. Applying this principle to compound keys, the reaction is "no way". Rails will do what it does, and will not complicate itself to support things it doesn't like.
Here is a solid example of what makes Rails "opinionated software". In the Rails mindset, life is much simpler if you keep your tables isomorphic to your objects, and give your tables surrogate, integer, primary keys. If you play the Rails way - life is easy; if not - use something else.
I confess I like this opinionated attitude. Perhaps it reflects my Unix background, which thrives on many tools that do one thing well, rather than a complex tool that tries to do many different things. I like Rails's focus, its determination to pick a certain class of application and serve that well.
In this sense I see a startling parallel between DHH and Kent Beck. For either of them, if you present them with a constrained world, they'll look at constraints we take for granted, consider them to be unessential, and create a world without them. I don't have that quality, I tend to try to work within the constraints gradually pushing at them, while they just stick some intellectual dynamite under them and move on. That's why they can create things like Extreme Programming and Rails which really give the industry a jolt.
Lying under PragDave's talk was a deeper concern. Like me he's spent much of this life working with people who can't apply the dynamite. When you need data from a database that's run by a data management group and has run for a decade with compound keys, you can't just don a pair of cool sunglasses and blow the constraint away. One answer to this is to "change your organization or change your organization", but to those who can't should they be utterly abandoned by Ruby?
The last word of the last paragraph is the key to the answer. Rails is right, I think, to ignore the enterprisey world, but that doesn't mean that Ruby should. One of the great strengths of scripting languages, like Ruby, is their post-modern delight in diving into the muck of a chaotic software ecosystem. Ruby is a great place for other frameworks to fill the gaps left behind by Rails's opinions.
My colleague Badri gave a talk, that was sadly not very well attended, about one of these - rBatis. rBatis is a ruby port of the popular Java framework iBatis (led by Clinton Begin, another colleague). The port is being done by yet a third colleague Jon Tirsén. rBatis is still a work in progress but already it shows the same elements that made iBatis popular - fearlessly embracing the strength of SQL rather than just trying to hide it under layer of Query Objects. It also strengthens its appeal by making the most of Ruby - stealing many functions from Active Record (such as validation), and using convenient Ruby syntax rather than XML. (Is XML the hunchback of programming languages?) rBatis could be the answer to complicated database issues, still fitting into a Rails web-app, but introducing a different set of trade-offs. If you're comfortable with SQL, rBatis looks pretty damn simple. (BTW any Rubyists out there Sydney? We may need you to kidnap Jon's surfboard if work slows down on rBatis.)
All this tilts our perspective. Enterprise Rails may well be an oxymoron, but Enterprise Ruby is anything but. Indeed as I look at the way the enterprise world is going - a greater use of messaging, autonomous services featuring ApplicationDatabases, a post-modern acceptance of variety - the glue that doesn't set seems to be the ideal tool.
Although some people felt these talks implied that there was a rift appearing between the Davids, further conversation suggests to me any rift is founded on misunderstanding (now there's a mangled metaphor). PragDave's call wasn't for Rails to support these things but for the wider community to find a way. Similarly DHH's response was about the Rails core team; which hardly limits other peoples' efforts - as rBatis demonstrates. Furthermore DHH felt that most of PragDave's calls were consistent with the Core. The notion of a narrow core rails and a wider ruby world (including rails) supports both concerns - this is the strength of composing small tools.
However this wide-ruby / narrow-rails view of the world has a catch. I joked during my keynote that RailsConf was a sign of a failure of Rails - since if it was truly successful Rails would be too simple to need a conference. The underlying truth, however, is that Rails has become the keyword for Web apps (even Enterprise apps) in Ruby. I suspect we'll see more enterprisey people at RailsConf than at RubyConf, because Rails has got the attention. The consequence of this is that there's a danger that people will hear the opinionated nature of Rails as a statement about Ruby, and thus give the impression that Ruby isn't a suitable enterprise glue. That would be a shame.