there are many obstacles (pre-existing conditions, different legal context, national sensitivities etc) in general the EU strategy has been to agree common rul

there are many obstacles (pre-existing conditions, different legal context, national sensitivities etc) in general the EU strategy has been to agree common rules and standards. But there are also examples of common infrastructure, e.g. the Euro bills it will be interesting to see how this might develop for software related to public institutions