During 2011, we performed a deep analysis of the two finite elements software developed by the lab (Melina and Monjoie) in order to propose a new software in C++ with extended capabilities and more integrated tools. The results of this analysis lead us to keep the general philosophy of Melina software (unified variational approach) but with major evolutions : integrated meshing tools, new variational description allowing FEM, BEM and DG formulation in an unified framework, global and local finite element computations, new approach to take into account essential boundary conditions and high performance computing skills (multithread and GPU computation). This new development will partly be supported by the Simposium european project dedicated to Non Destructive Testing tools (leader CEA/LIST, from september 2011 to august 2014) which requires some numerical simulation tools such as finite element library. It also a collaborative project with IRMAR (Rennes University). This new library, named xlife++ for eXtended LIbrary of Finite Element in C++, is an open source library (LGPL license) and its repository is the INRIA Gforge.