The aim of the project is to expand and make available, under an open-source licence, the ZefirLib libraries and tools for defining the path of energy transition, both at local and national level. The expansion and availability of this advanced mathematical-programming tool is intended to create a community around it in order to improve the efficiency of cooperation between science and the business environment, including local authorities. The extension of the tool with a graphical module and a results analysis module will support the propagation of know-how necessary for the independent launch and development of the tool, which will also allow users to prepare multi-scenario energy transition scenarios.