Startup Coupa plans to launch next month a beefier commercial version of its open-source e-procurement software, which tries to carry over to corporate purchasing the consumer buying experience found on retail Web sites.

Ease of use is the mantra of the company that that has offered a free version of its software since early August. E-Procurement Express, downloadable from Coupa's Web site, is built on the open-source Web framework Ruby On Rails.

Founded by former Oracle executives Dave Stephens and Noah Eisner, Coupa hopes to find a place in the crowded e-procurement market by offering an Amazon.com-like user interface that would be familiar to most corporate employees. While the company's software doesn't have the features of offerings from larger vendors like Ariba, Oracle, and SAP, it may be all a midsize company needs for many of its purchases of goods and services.

"The shopping and buying experience for the average employee is much more like Amazon.com than what's in the traditional business application," Stephens said. "We just thought there was a growing disconnect from how people use the computer at home, and how they use it at work."

E-Procurement Enterprise, set for release in April, will be available as an online service or for in-house deployment. Suppliers' names, product numbers, descriptions, pricing, and other information are uploaded to the software as a flat file. Once the information is in the system, purchase orders can be created and sent through a preconfigured approval process before they are sent to the supplier via e-mail, through the company's Web store, or directly into its order-management system as an XML document.

Besides focusing on ease of use, Coupa also hopes the software's features for ordering services will act as a differentiator for its product. The software offers customizable Web forms that a company can send to its lawyer's office, for example, to request routine services.

E-procurement software, in general, is used by companies to buy office furniture, computer equipment, printers, office supplies, and other non-critical items. Coupa's software is meant to replace a mid-market company's use of paper spreadsheets, documents, and the fax machine for purchasing such items.

Coupa launched its free software as a way to get its product out in front of companies. "They can use it and get to know Coupa," Stephens said. "And who knows, they may want to upgrade to Coupa E-Procurement Enterprise." In the last seven months, there have been 3,000 downloads of the free product.

Coupa's investors include the venture capital firm BlueRun Ventures.