Refinement and Resolution of Just-in-Time Requirements in Open Source Software: A Case Study

Just-in-time (JIT) requirements are characterized as not following the traditional requirement engineering approach, instead focusing on elaboration when the implementation begins. In this experience report, we analyze both functional and nonfunctional JIT requirements from three successful open source software (OSS) projects, including Firefox, Lucene, and Mylyn, to explore the common activities that shaped those requirements. We identify a novel refinement and resolution process that all studied requirements followed from requirement inception to their complete realization and subsequent release. This research provides new insights into how OSS project teams create quality features from simple initial descriptions of JIT requirements. Our study also initiates three captivating questions regarding JIT requirements and opens new avenues for further research in this emerging field.