  Background: OSS projects face various challenges. One major challenge is to
onboard and integrate newcomers to the project. Aim: We aim to understand and
discuss the challenges newcomers face when joining an OSS project and present
evidence on how hackathons can mitigate those challenges. Method: We conducted
two searches on digital libraries to (1) explore challenges faced by newcomers
to join OSS projects, and (2) collect evidence on how hackathons were used to
address them. We defined four evidence categories (positive, inconclusive, and
no evidence) to classify evidence how hackathons address challenges. In
addition, we investigated whether a hackathon event was related to an OSS
project or not. Result: We identified a range of newcomer challenges that were
successfully addressed using hackathons. However, not all of the solutions we
identified were applied in the context of OSS. Conclusion: There seems to be
potential in using hackathons to overcome newcomers' challenges in OSS projects
and allow them to integrate faster into the project.
