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Cited by 36Open Source Software InnovationsSoftware Engineering ResearchSoftware Engineering Techniques and Practices

How has forking changed in the last 20 years?: a study of hard forks on GitHub

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Zhou, Shurui, Vasilescu, Bogdan, Kästner, Christian·2020·Proceedings of the ACM/IEEE 42nd International Conference on Software Engineering
DOI 10.1145/3377811.3380412
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Abstract

The notion of forking has changed with the rise of distributed version control systems and social coding environments, like GitHub. Traditionally forking refers to splitting off an independent development branch (which we call hard forks); research on hard forks, conducted mostly in pre-GitHub days showed that hard forks were often seen critical as they may fragment a community Today, in social coding environments, open-source developers are encouraged to fork a project in order to contribute to the community (which we call social forks), which may have also influenced perceptions and practices around hard forks. To revisit hard forks, we identify, study, and classify 15,306 hard forks on GitHub and interview 18 owners of hard forks or forked repositories. We find that, among others, hard forks often evolve out of social forks rather than being planned deliberately and that perception about hard forks have indeed changed dramatically, seeing them often as a positive noncompetitive alternative to the original project.

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  • Hard forks are different from social forks popularized by GitHub, which are often used for collaboration while contributing to the original project using a pull request model.

    “Hard forks are different from social forks popularized by GitHub, which are often used for collaboration while contributing to the original project using a pull request model (Negoita et al. 2019;Zhou et al. 2020;Overhage and Widjaja 2022).”

    From Freeriding and Rebellion: An Investigation of Open Source Vendor Relicensing and Member Hard Forking Events (2026) · cites this paper as Zhou et al. 2020

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Cited by

Sorted by citations

Authors
Zhou, S., Vasilescu, B., & Kästner, C.
Affiliations
Carnegie Mellon University (US)
ORCID
Venue
Proceedings of the ACM/IEEE 42nd International Conference on Software Engineering
Publisher
ACM
Published
2020-06-27
Pages
445-456
ISSN
0270-5257 (ISSN-L)
DOI
10.1145/3377811.3380412
OpenAlex
W3090035558
Cited by
36
References
2
Citations by year
2026: 4 · 2025: 6 · 2024: 2 · 2023: 6 · 2022: 6 · 2021: 10 · 2020: 2
FWCI
6.97
Type
conference paper
Language
en
Open access
Licence
www.acm.org/publications/policies/copyright_policy#Background (vor)
Locations
  • ACM/IEEE International Conference on Software Engineering: Companion Proceedings (ICSE-Companion) (publishedVersion)
  • Zenodo (CERN European Organization for Nuclear Research) (submittedVersion, cc-by)
Funders
National Science Foundation (1552944, 1717022, 1813598)
Topics
  • Physical Sciences › Computer Science › Computer Science Applications › Open Source Software Innovations
  • Physical Sciences › Computer Science › Information Systems › Software Engineering Research
  • Physical Sciences › Computer Science › Information Systems › Software Engineering Techniques and Practices
Keywords
forking, hard forks, distributed version control systems, GitHub, open source software, developer communities, community fragmentation, developer perceptions

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