When QC calculations are used to calculate various physical and chemical properties or phenomena, arbitrary values might be obtained even for the same molecule due to the different computation processes. To avoid this, a standard computation process should be provided. Especially, standardized computation process as is in QCforever would be important for building a database based on QC calculation. As the demonstration of QCforever, we computed 100 molecules picked up from ZINC database. Although the current QCforever could not exclude the several failures including the molecules that have the negative vibrational modes, the computation of 90% of molecules succeeded. In the near future, we will develop QCforever to deal with the negative vibrational mode and several failures like AiiDA. Simulation tools are expected to reduce the difficulty to develop new materials. QC computation was also one of them. In practice, however, QC is mainly used as a tool giving speculation to chemical phenomena. The history of QC proves that it is a powerful tool to get plausible answers to the forward problems where input is molecules. On the other hand, QC is also used for finding the expected molecules for chemical synthesis in experimental chemistry laboratories. This process corresponds to an inverse problem where we should deal with the diversity of the chemical compounds. Surely, the search space is restricted within professional knowledge and favor. Combining QCforever with the black-box optimization algorithm, we can remove this restriction and bias and expand the search space.