  The implementation and engineering of bright and coherent solid state quantum
light sources is key for the realization of both on chip and remote quantum
networks. Despite tremendous efforts for more than 15 years, the combination of
these two key prerequisites in a single, potentially scalable device is a major
challenge. Here, we report on the observation of bright and coherent single
photon emission generated via pulsed, resonance fluorescence conditions from a
single quantum dot (QD) deterministically centered in a micropillar cavity
device via cryogenic optical lithography. The brightness of the QD fluorescence
is greatly enhanced on resonance with the fundamental mode of the pillar,
leading to an overall device efficiency of $\eta=(74\pm4)~\%$ for a single
photon emission as pure as $g^{(2)}(0)=0.0092\pm0.0004$. The combination of
large Purcell enhancement and resonant pumping conditions allows us to observe
a two-photon wave packet overlap up to $\nu=(88\pm3)~\%$
