This package was supposed to implement network-level operations for tensor networks, such as automated and efficient finding of optimal contraction orders, automatic differentiation like features such as taking subnetworks and environments, etc. A bunch of supporting architecture was put in place but none of the main meat is there yet. I haven't touched this for a few years now (as of early 2020) and doubt I'll have time to do so in the near future, but if someone wants to use this as a starting point, please feel free.