[objectified]

I recently created vdist (https://vdist.readthedocs.org/en/latest/ - https://github.com/objectified/vdist) for doing similar things - the exception being is that it uses Docker to actually build the OS package on. vdist uses FPM under the hood, and (currently) lets you build both deb and rpm packages. It also packs up a complete virtualenv, and installs the build time OS dependencies on the Docker machine where it builds on when needed. The runtime dependencies are made into dependencies of the resulting package.