EBay Inc.'s evolution into a full-fledged technology environment continued Tuesday when the company said it would soon add Simple Object Access Protocol APIs and Java integration tools into the mix of Web-services offerings available to its developer community. The added resources are expected to yield a wider array of applications that buyers and sellers can use to support their transactions on eBay, as well as boost eBay revenue by fueling additional transactions. During 2003, 95 million registered eBay users bought and sold more than $23 billion worth of goods on the site.

The addition of Soap and Java capabilities, expected to be available in the second quarter, is a response to requests from developers who have been limited to XML and .Net when building apps for eBay. Debbie Brackeen, director of the eBay Developers Program, says the new tools will let eBay reach a larger developer audience--this, in turn, will mean new capabilities for buyers and sellers. "There's going to be a much larger and richer set of applications to facilitate their buying and selling on the marketplace," Brackeen says.

In the past year, eBay's developer community has mushroomed from fewer than 200 members to more than 4,000, and they're building all kinds of applications that are expanding the eBay trading model. Companies such as Andale, Auctionworks, and ChannelAdvisor have built businesses providing auction-management applications to eBay buyers and sellers. Highline Technologies has established its auction technology specifically as a tool to help more than 400 auto dealers sell thousands of cars on eBay, most recently providing an application that lets dealers list cars directly from their lots using mobile devices. And even SAP has built plug-ins for its mySAP and R/3 products so that its customers can automate the listing of excess or out-of-date inventory on eBay.

Sometimes, developers have sprung from more unlikely places. For instance, SuperPawn, which relies on eBay as one of the channels through which it sells used goods, used eBay's Web services development tools to build an application, called AuctionMonitor, that linked its point-of-sale system directly to eBay--streamlining the process of listing, categorizing, and fulfilling merchandise. The application proved so effective that SuperPawn formed a second company, zTradingPost.com, so that it could resell that application to other retailers.

Limited access to the Soap APIs and Java tools will be free, while broader access will be accompanied by fees ranging from $500 to $5,000 a year.