QuickFIX is the worlds first Open Source C++ FIX (Financial Information eXchange) engine, helping financial institutions easily integrate with each other.
The SVN repository is now locked. Latest code is hosted at github.
https://github.com/quickfix/quickfix
The Marketcetera Trading Platform is a comprehensive open-source software infrastructure for algorithmic trading, that is a true alternative to expensive, monolithic proprietary systems or brittle software mashups.