We present the design and its' implementation for a flexible and robust modular finite element framework, called ModFem. The design is based on reusable modules which use narrow and well-defined interfaces to cooperate. At the top of the architecture there are problem dependent modules, with the main module being an incompressible flow solver. Problem dependent modules can be additionally grouped together by" super-modules", eg for the purpose of applying created codes for multi-physics and multi-scale problems. Additionally, the framework tries to provide suitable infrastructure for parallel computations, at the level of shared memory, as well as distributed memory systems.