  Media with engineered magnetization are essential building blocks in
superconductivity, magnetism and magnon spintronics. However, the established
thin-film and lithographic techniques insufficiently suit the realization of
planar components with on-demand-tailored magnetization in the lateral
dimension. Here, we demonstrate the engineering of the magnetic properties of
CoFe-based nanodisks fabricated by the mask-less technique of focused electron
beam induced deposition (FEBID). The material composition in the nanodisks is
tuned \emph{in-situ} via the e-beam waiting time in the FEBID process and their
post-growth irradiation with Ga ions. The magnetization $M_s$ and exchange
stiffness $A$ of the disks are deduced from perpendicular ferromagnetic
resonance measurements. The achieved $M_s$ variation in the broad range from
$720$ emu/cm$^3$ to $1430$ emu/cm$^3$ continuously bridges the gap between the
$M_s$ values of such widely used magnonic materials as permalloy and CoFeB. The
presented approach paves a way towards nanoscale 2D and 3D systems with
controllable and space-varied magnetic properties.
