Fix8 is an open source FIX engine written in C++ (released under the Lesser GPL license). Fix8 helps you get your FIX client or server up and running quickly. Using one of the standard FIX schemas you can have a FIX client or server up and running in next to no time. Statically compile your FIX xml schema and quickly build your FIX application on top. If you need to add customised messages or fields, simply update the schema and recompile. Fix8 supports FIX4.X to FIX5.X and FIXT1.X. New FIX versions will be supported. Fix8 offers run-time custom fields, message recycling and a meta-data aware test harness. Incorporates lock free queues, atomics and many other modern techniques. Fix8 is a complete C++ FIX framework, including client/server session and connection classes; support for the standard FIX field types; FIX printer, async logger, async message persister and XML configuration classes. Fix8 statically supports nested components and groups. The Fix8 compiler and runtime library takes the pain out of using repeating groups. The code generated by Fix8 is compiled by your compiler offering the best opportunity for optimisation. Fix8 applications are fast. Typical encode latency is now 16us, and decode 17us. This is being improved further. Fix8 has been designed to be extended, customised or enhanced. If you have special requirements, Fix8 will facilitate your development.  Fix8 runs on industry standard Linux. Other *NIX variants may work too.