For the record in the interest of programmers who don't use Erlang on a daily basis: It is very common to use Erlang as a "glue" system between other subsystem

For the record in the interest of programmers who don't use Erlang on a daily basis: It is very common to use Erlang as a "glue" system between other subsystems in larger installations. You will often find the Erlang system controlling code written in other languages, for different reasons: The large Java subsystem which is hard to replace. The C/C++ code you run as a hidden node() in the Erlang distribution cluster. The C-accelerated function you added to the Erlang BEAM VM through dynamic loading of a .so (called a NIF). The OCaml or Go program you communicate with through a port (essentially an Erlang-controlled pipe with a proxy light-weight process inside the Erlang VM). And so on. Some times, the right tool for the job is another system. The tool 'py' provides yet another such bridge which allows you to interact with Python programs in a very direct way.