The Senior Hypervisor Engineer role at Nebius focuses on enhancing the hyperscaler platform by improving the KVM hypervisor and QEMU device emulator. Key responsibilities include optimizing I/O for devices, integrating hypervisor services, distributing virtual machine resources, and enhancing guest system support. Candidates should have over five years of software engineering experience, proficiency in C, and a strong background with Linux and QEMU/KVM.