Imported from previous forum
I am currently updating some parts of our FIX engine which are generated partially using the contents of the FIX repository from fix-repository_20090420.zip. When I started to adapt to the FIXRepository-2010-Edition_rel-20100620.zip I note that making the solution handle both formats will yield a solution which has more maintenance issues than I would like (it would be a mess!). So, are we expecting the new format from 2010 to be stable for a while, or am I to expect format changes in the next release? If a new release is imminent with a new format then we might as well stick to the old format for our next release, otherwise we will move to the latest format.
This is a great question.
To your point we are working on a 2012/2013 repository edition which will have changes to the 2010 format.
However, we are going to make the changes forward compatible, meaning that even if we have to duplicate a bit of data, someone that has written to 2010 repository (and I would strongly recommend you use the unified repository format) should find their application will work with later versions - at least the next version.
Point is from a philosophical perspective, the goal is to avoid breakage to every extent possible. Should we introduce breakage, we better have a darned good reason that would justify having the FIX Community need to modify their applications. Any breakage would be widely vetted and justified and hopefully accepted across the FIX Community.