We demonstrate a new integrated open-source tool-set for Control, Calibration and Characterization (C3)  by applying it to a simulated example of a two-qubit quantum processor. We illustrate our methods using fixed-frequency superconducting qubits for which we perform open-loop optimal control to derive high-fidelity single-qubit gates. We calibrate those gates on a blackbox simulation by performing single-length Randomized Benchmarking sequences. We use the calibration data to improve the model of the system and thus are able to derive a coherence limited cross-resonance (CR) gate that achieves 99.6% fidelity without need for any calibration.  Wittler, N., Roy, F., Pack, K., Werninghaus, M., Roy, A. S., Egger, D. J., Filipp, S., Wilhelm, F.K., Machnes, S. (2020). An integrated tool-set for Control, Calibration and Characterization of quantum devices applied to superconducting qubits. arXiv:2009.09866 *This work was supported by the European Commission through the Marie Curie ETN QuSCo (Grant Nr. 765267) and the OpenSuperQ project (Grant Nr. 820363), by the Intelligence Advanced Research Projects Activity (IARPA) through the LogiQ (Grant Nr. W911NF-16-1-0114) and by the Germany Ministry of Science and Education (BMBF) through project VERTICONS (Grant Nr. 13N14872).