  This paper describes Nancy, a Network Calculus (NC) library that allows users
to perform complex min-plus and max-plus algebra operations efficiently. To the
best of our knowledge, Nancy is the only open-source library that implements
operations working on arbitrary piecewise affine functions, as well as to
implement some of them (e.g. sub-additive closure and function composition).
Nancy allows researchers to compute NC results using a straightforward syntax,
which matches the algebraic one. Moreover, it is designed having computational
efficiency in mind: it exploits optimizations of data structures, it uses
inheritance to allow for faster algorithms when they are available (e.g., for
specific subclasses of functions), and it is natively parallel, thus reaping
the benefit of multicore hardware. This makes it usable to solve NC problems
which were previously considered beyond the realm of tractable.
