FELTOR (Full-F ELectromagnetic code in TORoidal geometry) is both a numerical library and a scientific software package built on top of it. Its main physical target are plasma edge and scrape-off layer (gyro-)fluid simulations. The numerical methods centre around discontinuous Galerkin methods on structured grids. Our core level functions are parallelized for a variety of hardware from multi-core cpu to hybrid MPI+GPU, which makes the library incredibly fast.