We evaluate the performance of hybrid microwave resonators made by combining sputtered Nb thin films with Tungsten nanowires grown with a He-beam induced deposition technique. Depending on growth conditions the nanowires have a typical width $win[35-75]$~nm and thickness $tin[5-40]$~nm. We observe a high normal state resistance $R_{sq}in [65-150]$ $Omega/sq$ which together with a critical temperature $T_cin[4-6]~K$ ensure a high kinetic inductance making the resonator strongly nonlinear. Both lumped and coplanar waveguide resonators were fabricated and measured at low temperature exhibiting internal quality factors up to $3990$ at $4.5$~GHz in the few photon regime. Analyzing the wire length, temperature and microwave power dependence we extracted a kinetic inductance for the W nanowire of $L_Kapprox15$ pH/sq, which is 250 times higher than the geometrical inductance, and a Kerr non-linearity as high as $K_{W,He}/2pi=200 pm 120$~Hz/photon at $4.5$~GHz. The nanowires made with the helium focused ion beam are thus versatile objects to engineer compact, high impedance, superconducting environments with a mask and resist free direct write process.
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