The c++ program FastImp is a wideband impedance extraction program for 3D geometries. It can perform Magneto-Quasi-Static (MQS), Electro-Magneto-Quasi-Static (EMQS) and fullwave analysis of complicated 3D structures from zero frequency to at least tens of Giga Hertz. These 3D structures are commonly seen in interconnects and packages of VLSI circuits. FastImp has two main components, a wideband surface integral formulation and a fast integral equation solver pfft++. It uses the boundary element method to discretize the surface formulation and uses a Pre-corrected FFT accelerated matrix-free iterative linear system solver to solve the large system matrix equation. FastImp was developed on Redhat Linux 7.2 with GNU gcc/g++ 2.96 as its compilers and GNU make as its builder. We have successfully ported the code to Compaq Unix with true64 c++ compiler with minor modification to the makefile and no change to source code. Please let us know of successes / failures on other platforms and architectures.