Salesforce.com buying Heroku sent shockwaves through the cloud community this week, but Salesforce.com wanting to get in on the Ruby action should come as no surprise. In the PaaS world, its popularity among developers is hard beat. But Ruby is just part of the emerging multi-language PaaS landscape. And in the race to win developer support, providers supporting a multitude of programming languages and frameworks will be the ones to thrive. After all, there’s no guarantee that developers will stick one language for all their applications, so flexibility is key. And if you have a good product from the start, why limit its scope?

Java, .NET and a Whole Lot More

At last month’s Ruby Conference, VMware unveiled a hosted PaaS offering, called Cloud OS, that will support Ruby, Python, .NET, and node.js, as well as Java. The provider joins Microsoft (with Windows Azure) and Red Hat (with Makara) as vendors with strong ties to the past embracing the future with PaaS offerings that extend beyond those companies’ respective .NET and Java roots. There’s distinct value in each vendor’s PaaS (and overall cloud) strategies, but restricting them to a single set of developers likely would prove too limiting.

Aside from those vendors, pure cloud players such as Google and Joyent are taking PaaS in their own directions. Google supports Spring-based Java with App Engine for Business, but Python is at the foundation of App Engine. Joyent, for its part, is pushing the JavaScript project Node.js with its SmartPlatform offering. In fact, Joyent now runs the Node.js project and employs its lead developer, and SmartPlatform, which runs atop the company’s SmartDataCenter software, will help companies build PaaS capabilities in-house.

If you’re wondering why Salesforce.com paid a respectable $212 million for Heroku, here’s your answer. Salesforce.com had a cloud strategy focused on Apex, a language very few care about, and Spring-based Java, which many more care about. Now, it can claim support for Ruby, which might be superior to Java for cloud development. The thousands of users hosting applications atop Heroku and Engine Yard are a testament to this notion. And if Heroku expands into other languages as has been suggested, Salesforce.com gets even more developers. More developers means more money upfront, and a lot more money when their employers decide to bless that use and make those platforms part of their cloud strategies going forward.

Is Engine Yard Due for a Big Payday?

Given all of this, the biggest winner might end up being the other Ruby on Rails PaaS provider, Engine Yard. CEO John Dillon and Founder and CTO Tom Mornini both indicated to me that the company is for sale for the right price. Mornini said he is “really happy” about the price Heroku commanded. He believes the speed of development and deployment with Ruby makes it superior to Java in the cloud, and that Salesforce.com’s decision to buy Heroku for such a high price validates Engine Yard’s stance that “Ruby is absolutely enterprise-ready.” Reading between the lines, Mornini seems to think that Engine Yard — which takes a more enterprise-friendly approach to PaaS, in terms of both architecture and service provider hosts — can command a price even higher than what Heroku got.

Considering how big a pain Salesforce.com is becoming for Oracle — first with CRM applications, then with Database.com and now with application platforms — it wouldn’t be surprising to see Oracle finally get its cloud act in gear and come knocking on Engine Yard’s door. Or maybe rumored former suitor VMware wants another bite at the apple. Either one could use a Ruby foundation to complement their flagship Java offerings.

Java Has a Place, Too

But none of this means Java doesn’t have a place in the cloud. As I wrote last week, the marketplace of PaaS offerings supporting Java has multiplied seemingly overnight. Despite their dalliances with Ruby and other languages, VMware and Red Hat still focus on Java (in one form or another). Whatever Oracle does, you can bet Java will play a big role. And Microsoft still places .NET at the forefront of its cloud offerings. It’s possible, in fact, that with more Java platforms available, Java developers will start flocking to the cloud and dominate there like it has in the on-premise world. Either way, PaaS is the future of cloud computing, and providers supporting the gamut of languages stand to make lots money regardless which languages carry the day.

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