That is, it's not just an online service where people buy and sell. It's also a back-end system enabling merchants to make sales without requiring buyers to be on eBay.com -- a back-end system on which developers can create applications to facilitate and expand the process. And a system in search of more developers.

"You know you're a platform when someone builds something on top of [you] that you couldn't predict," said eBay founder Pierre Omidyar, speaking before a crowd of third-party eBay developers in New Orleans yesterday, at the auction site's first developer conference. "There are some markets and segments that we simply can't reach, because we've got to prioritize things, and so forth."

eBay is making a big push to woo developers into creating applications that drive traffic to its auctions and stores, and otherwise, build on its systems. That's part of the reason behind eBay's developer conference here, and recent moves to provide more extensive developer tools.

The e-commerce giant is wagering that by courting third-party developers, who can bake in eBay technology and products into their own sites and services, it can expand into new markets, media or technologies -- like mobile, for instance -- thereby increasing its number of buyers, auctions, and sales.

During an afternoon keynote session yesterday, Omidyar and tech publishing giant Tim O'Reilly spoke, in part, about the different ways that developers can leverage eBay.

Speaking before the audience of developers, O'Reilly compared eBay's reputation system to Microsoft's PassPort -- and suggested that eBay, with its feedback and trusted payment systems, might have the tools to make an Internet-wide identity scheme a reality.

"People come to eBay because they know they can trust people on eBay," Omidyar said in response. "A large part of that is the reputation system that exists there. They can also use PayPal at eBay and make it a trusted payment. I think the combination of the reputation information, the payment system ... is an credible powerful system that can act as an identity for somebody as they travel through the Internet."

"We'll see what the smart people in this room can come up with," he added.

O'Reilly also suggested that eBay developers might make use of the massive stores of data that the auction site generates, as it relates to concepts such as pricing or supply and demand. Intuit's popular accounting program, QuickBooks, for instance, can glean data from eBay to determine valuations for goods.

"The idea is that the value isn't just in software, but in data," he said. "The Intuit relationship ... the idea, for example, of QuickBooks and Quicken looking up the price of items on eBay, strikes me as fascinating."

Added Omidyar, "There's a lot of information being generated ... about what market trends are. Intuit found one logical use for it; others have found others. I think there are probably more out there."

Additionally, O'Reilly said eBay developers might innovate successfully by linking outside data to eBay auctions.

"There are certain marketplaces where information about products is fairly critical," he said. "Selling books is still easier to do on Amazon, because they effectively have all the data about the book. I wonder if that's an opportunity for developers -- to provide not just interfaces, but data repositories."

Omidyar also addressed what some buyers might call the "dark side" of eBay development -- "sniping" tools that allow buyers to swoop in, seconds before the close of an auction, and place an unexpected, winning bid. But he declined from saying whether eBay would eventually allow for extending auctions in the event of sniping.

"I think sniping is an interesting phenomenon," he said. "And as I explain to the victims of sniping, the snipers take risks -- technology makes snipers more efficient than they used to be, but whatever you do, there are pros and cons." Developing on eBay -- making the pitch
Omidyar said that while developing a Web-centric application may be difficult, the rewards can be greater than working with traditional, packaged software.

"Developing for the Web is fundamentally different -- it's much more rapid, he said. "It increases your blood pressure much more than [traditional software]. You put something out there and if it's wrong or consumers hate it, they tell you right away ... and you've got to fix it right away.

"But, the way I think of it is, instead of building big, big applications that you deliver and say, 'Look customer, isn't this what you wanted? Isn't it perfect?', you build a little at a time," he said. "You get feedback on what you're serving, and [users] say, 'This is broken,' and we say, 'Oh you're right, this is broken, let's fix it.' You're ultimately going to end up with much higher-quality software."

Omidyar also recommended that developers help eBay understand what it can do to better support their efforts to facilitate buying and selling -- or creating technologies that can extend eBay's functionality to new media or markets.

"As you discover those types of things, definitely communicate to platform and developer team what you need to make your applications more successful," he said. "The role of eBay ought to be to provide tools on the platform, to continue to provide tools that enable new forms of trade."

"Developers [can] move beyond providing new tools and software, which enables new things -- fantastic things," Omidyar added. "At eBay, it's always been about our community, and helping our community be successful -- and it's great that we've expanded the definition of our community to people building tools. We and our community will be enriched by your active participation."

Christopher Saunders is managing editor of eCommerce-Guide.com.

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