The increasing popularity of Ajax (Asynchronous JavaScript and XML) will be in evidence this week when integration giant Tibco Software announces free building and testing of applications created on the development platform as part of a new version of its General Interface.

Ajax has gathered momentum as a way of developing composite applications – for example, dynamic combinations of services for sales-tracking systems over maps.

Best known from consumer services such as Google and Yahoo, Ajax is widely expected to become more broadly incorporated in developer toolkits and interfaces to enterprise applications.

Tibco’s General Interface 3.1 Professional Edition will allow firms to build Ajax applications and deploy them publicly at no cost, according to the vendor. Private-use applications will carry a tariff, however.

“Our attitude is that if it’s a public application then it’s free, but if you want to use it behind a password you have to pay a licence,” said Kevin Hakman, Tibco director of product marketing.

Tibco said it has used Ajax technologies for several years but argued that the technology is now “mature” in the General Interface, thanks to visual integration and usability enhancements.

Meanwhile, IBM is pushing a project called Open Ajax, designed to simplify use of Ajax with the open-source Eclipse toolkit.

Tibco’s General Interface is also being used in RFID wireless tagging projects, including an ambitious effort by logistics company TNT to track parts used by Ford to manufacture cars.