The gRPC protobuf plugin requires that libprotoc is in your LD_LIBRARY_PATH. Until we figure out a general solution, you may need to do:

export LD_LIBRARY_PATH=$PROTOBUF_HOME/lib:$LD_LIBRARY_PATH

Currently, to run the unit tests, the directory of executables must either be your current working directory or you need to add it to your path, e.g.

PATH=debug:$PATH debug/flight-test