Open-source software (OSS) projects depend on community engagement (CE) for longevity. However, CE's quantifiable impact on project dynamics and lifespan is underexplored. Objectives: This study defines CE in OSS, identifies key metrics, and evaluates their influence on project dynamics (releases, commits, branches) and lifespan. Methods: We analyzed 33,946 GitHub repositories, defining and operationalizing CE with validated per-month metrics (issues, comments, watchers, stargazers). Non-parametric tests and correlations assessed relationships with project dynamics and lifespan across quartiles. Results: CE metrics significantly associate with project dynamics, with stronger correlations in highly engaged projects. For lifespan, a complex pattern emerged: per-month CE rates are highest in younger projects, declining with age. Yet, a subset of long-lived projects maintains exceptionally high activity. Initial CE bursts appear crucial for establishment, while sustained high engagement drives extreme longevity. Active issue engagement's influence intensifies with age, but passive attention's declines. Conclusion: CE dynamically drives OSS project longevity and development. Our findings establish validated CE metrics and offer deeper insights into how diverse community activity patterns contribute to project longevity.

翻译：开源软件（OSS）项目的长期存续依赖于社区参与度（CE），然而CE对项目动态及生命周期的量化影响尚未得到充分探究。本研究旨在：明确OSS中CE的定义，识别关键度量指标，并评估其对项目动态（版本发布、提交记录、分支）及生命周期的影响。方法：我们分析了33,946个GitHub代码库，采用经验证的月度指标（问题提交、评论、关注者、星标数）对CE进行定义与量化。通过非参数检验与相关性分析，评估了CE与项目动态及生命周期在四分位分组中的关联性。结果：CE指标与项目动态显著相关，在高参与度项目中相关性更强。在生命周期方面呈现复杂模式：月度CE率在新生项目中最高，并随项目年龄增长而下降；但部分长期存续的项目仍能保持极高的活跃度。初始的CE爆发对项目建立至关重要，而持续的高强度参与则驱动极端长寿。议题参与度的影响随项目年龄增长而增强，而被动关注度的影响则逐渐减弱。结论：CE动态驱动着OSS项目的存续与发展。本研究建立了经过验证的CE度量体系，并为理解多样化社区活动模式如何影响项目生命周期提供了更深入的见解。