Free, Fast, Native.
The best FIX Engine for .NET
QuickFIX/n implements the FIX protocol on .NET.
QuickFIX/n is 100% free and open source with a liberal license.
Commercial support provided by Connamara Systems.
FIX is an electronic messaging protocol for financial transactions. The Financial Information eXchange (FIX) is an open, widely used industry standard. More information is available on the FIX protocol website.