C12 builds next generation quantum computers powered by the most elementary material: carbon nanotubes. By utilizing single-electron spins hosted in suspended ultra-clean carbon nanotubes, we achieve the closest realization of an ideal spin qubit in vacuum. We integrate the nanotubes onto semiconductor chips thanks to our proprietary high-throughput technique. Thereby, we achieve isolated yet easily addressable qubits. Our carbon nanotube based technology can scale quantum computing, in the vein of what silicon did for classical computing. Combining the purity of carbon nanotubes and well-established semiconductor manufacturing, our innovation has the potential to process quantum information at large scale with the highest fidelity.