Nanoparticle-doped fibers are a promising way to extend functionalities of optical fibers. We are exploring glass powder doping for incorporating nanocrystals (NCs) into fibers, where the NCs survive the drawing process in its crystalline phase. For a first proof-of-principle, we are using YPO4:Yb3+ NCs that successfully survived the fiber drawing as confirmed by x-ray diffraction, TEM, and fluorescence analysis. The NC synthesis and characterization as well as the powder mixing process, sintering, and fiber drawing processes will be presented. In a series of experiments, the maximum Yb doping of 20 at% in the NCs was established as well as the maximum NC content of 7 wt% in the fiber core. A first amplification experiments yielded an on-off gain coefficient of about 1 dB/cm.