Many software engineering studies or tasks rely on categorizing software engineering artifacts. In practice, this is done either by defining simple but often imprecise heuristics, or by manual labelling of the artifacts. Unfortunately, errors in these categorizations impact the tasks that rely on them. To improve the precision of these categorizations, we propose to gather heuristics in a collaborative heuristic repository, to which researchers can contribute a large amount of diverse heuristics for a variety of tasks on a variety of SE artifacts. These heuristics are then leveraged by state-of-the-art weak supervision techniques to train high-quality classifiers, thus improving the categorizations. We present an initial version of the heuristic repository, which we applied to the concrete task of commit classification.