The year 2025 has been declared the International Year of Quantum Science and Technology (IYQ) by UNESCO, following the past few years of accelerated progress in the development of quantum technologies. The breadth and scope of applications has dramatically increased, expanding the diversity of quantum systems of interest, in particular in the solid state. This has led to an increase in the complexity of these systems, tightening the requirements on materials, interfaces and integration, in turn dictating improvements in synthesis and fabrication. In order to foster interdisciplinary collaborations on these topics, we propose to organize two two-day workshops in Paris aiming to bring together specialists in materials synthesis, fundamental spin dynamics in solids, and a diverse range of quantum applications. The workshop will include both formal presentations and open discussion time to foster new ideas and collaborations on materials and spin qubit discovery, materials optimization for given applications, understanding of spin dynamics and decoherence, innovative approaches to quantum applications, and interfacing different quantum systems. We aim to make this workshop a yearly platform for the exchange of ideas, students, postdocs and for the development of collaborations in the long term.