In this regard, we have provided a library of all of the torsional parameters derived in this study, and these could be used as initial estimates for approximate dynamics, or as an initial guess in the fitting process. Improper torsional parameters are not derived in this study, and we have used those from the OPLS FF here. Potential future improvements include support for 2D torsion scans, and the use of direct fitting to the Hessian matrix to allow derivation of stiff, harmonic torsional parameters and cross-terms to account for coupling between internal coordinates. Such improvements are especially important in, for example, spectroscopic applications where a faithful representation of the QM intramolecular potential energy surface is crucial. We have provided with this paper the QUBEKit software toolkit, tutorials and data sets (). This first version utilizes the BOSS molecular mechanics software, and Gaussian09 61 and ONETEP QM packages for parameter derivation. Simulation-ready files are output in OpenMM, Gromacs or BOSS format. Future work will widen the choice of available software, particularly for parameter derivation. Additional validation of QUBE against metrics such as condensed phase dielectric constants, hostguest binding and many more are envisaged, and we hope that QUBEKit will facilitate this process. In parallel, we are also releasing the QUBE protein force field, which employs the same non-bonded parameter derivation techniques implemented in linear-scaling DFT software, 106 alongside a torsion library for the twenty naturally-occurring amino acids. Together these tools will allow users to derive compatible and accurate QUBE force fields for both proteins and small molecules for use in computer-aided drug design applications.