BAGEL, Brilliantly Advanced General Electronic-structure Library Open-source version of QSimulate-QM; QSimulate is committed to maintain the open source BAGEL. *** Website *** http://www.nubakery.org *** Citation *** Please cite as: "BAGEL, Brilliantly Advanced General Electronic-structure Library. http://www.nubakery.org under the GNU General Public License." A review can be found at: WIREs Comput. Mol. Sci 8, e1331 (2018). DOI: 10.1002/wcms.1331 *** License *** BAGEL is distributed under the GPLv3+. *** Disclaimer *** BAGEL is intended for use in parallel environments with a large amount of distributed memory (e.g., hence there is no disk interface). We are NOT going to optimize BAGEL for a stand-alone workstation. BAGEL is being tested primarily on Linux (CentOS and SUSE) and MacOS that we have access to. Since the program is standard compliant, it is expected that BAGEL also works on other platforms.