Great that it’s built and running for you now.
The ORE dir will be big as by default we build all of boost and QL, and there are a number of small sub-libraries that we also don’t need.
If you want to have a portable build of the ore executable on linux, rather than stripping down the build directory, you should just extract the bits you need. I suggest you try to build a static version of ore executable (by default the unix builds use dynamic libraries). On my Mac, my ORE dir is 4.2GB, but when I build a static ore exe it’s only 24MB (you will need the input files of course)
To do this just manually link the ore object (ore.o) in App with all the required (static) libraries: QL, ORED, OREA and whatever boost ones are needed (there are 3 or 4 of them, have a look in App/Makefile.am), then see if that is small enough for you. Then there are tools for stripping the exe down further if you research it on the net.
Does that help? what exactly are you trying to do here? ORE was never designed to be particularly small, I’m not sure if it’s suited for a constrained device, Pi or something like that.