Imported from previous forum
The Open Source QuickFIX project has released the newest version of it’s FIX engine. This is a fully functioning FIX engine, with source, not crippled in any way. Versions supported are FIX 4.0-4.4. Core engine implemented in C++ with Java and .NET wrappers. Builds on Windows, Linux, Solaris, FreeBSD, and Mac OS X. This is not a press release, this is an actual piece of software available for download now at http://quickfix.thoughtworks.com
QuickFIX was first released in 2001 and has been running in production systems for over 2 years.