When it breaks, it breaks: How ecosystem developers reason about the stability of dependencies

Dependencies among software projects and libraries are an indicator of the often implicit collaboration among many developers in software ecosystems. Negotiating change can be tricky: changes to one module may cause ripple effects to many other modules that depend on it, yet insisting on only backwardcompatible changes may incur significant opportunity cost and stifle change. We argue that awareness mechanisms based on various notions of stability can enable developers to make decisions that are independent yet wise and provide stewardship rather than disruption to the ecosystem. In ongoing interviews with developers in two software ecosystems (CRAN and Node.js), we are finding that developers in fact struggle with change, that they often use adhoc mechanisms to negotiate change, and that existing awareness mechanisms like Github notification feeds are rarely used due to information overload. We study the state of the art and current information needs and outline a vision toward a change-based awareness system.