Open Forex Platform is an open source financial instruments trading platform. It allows development of custom strategies and experts as well as conventional manual trading and back testing. The platform has the capability to integrate with other platforms to allow trading and data acquisition. The platform requires .NET Framework 3.0 or later to run.
The home page of the project is :
http://www.openforexplatform.comThese are a couple screen shots from the platform in operation:


Connectivity diagram illustrating the connectivity capabilities of the Platform (click for larger image)
