OrbitSI using NetworkX for Python

OrbitSI is a NetworkX-based Python package that efficiently solves the subgraph isomorphism enumeration problem, i.e., finding all subgraphs in a large data graph Gd that are isomorphic to a pattern/query graph Gp. It also supports fast vertex orbit counting, which summarises the local structural roles of vertices within a network. OrbitSI combines orbit-based filtering and ordering to prune and order candidate node mappings, significantly reducing the search space during subgraph matching. It integrates two state-of-the-art orbit counting engines — EVOKE and ORCA — via optimised C++ bindings using pybind11, and builds the search pipeline using networkx. The package includes a command-line interface (CLI), usable library, and testing utilities. It is installable via pip, tested on synthetic and real-world benchmark datasets, and fully open source under the Apache 2.0 license.