For the next use case, we were interested in tracking how well various machine-learning algorithms and descriptors perform at building predictive models on the SIMPD bioactivity data sets . Here, we initialized the database by registering all of the compounds from each of the SIMPD data sets. During this setup process, the lwreg database was extended to include a schema that included a registry of data sets. The registration system was configured to use the ChargeParent standardization, automatically capturing only the largest organic fragment from each compound and neutralizing it. Metadata about the machine-learning runs and the results of the experiments on the individual data sets was stored in another set of tables in the database. An example of how to set up and use these tables is present in the tutorial folder of the lwreg repository.