I've done nearly the same thing and have called it 'keyd' as well.

It's a little more inspired by a "djb" style design. Instead of having a configuration file, the program takes a single argument which is meant to be a directory. Then, if code 113 is pressed, it looks for an executable file named '113' in the given directory and if it exists will execute it. If not found it then tries '113+', then on release it will try '113-'.