What is it written in?
ORE is written in C++. ORE consists of three libraries (QuantExt, OREData and OREAnalytics) and a command line application that demonstrates how ORE’s functionality can be used. QuantExt uses C++98 in line with QuantLib and to facilitate migrating code from QuantExt to QuantLib over time. The Data and Analytics libraries use C++11 for convenience.