Evolutionary Trends of Developer Coordination: A Network Approach

TL;DR

This study investigates how developer coordination evolves in large open-source projects using network analysis, revealing scale-free, hybrid, and hierarchical structures that balance coordination costs and benefits.

Contribution

It introduces a longitudinal network-analytic approach to uncover organizational principles governing developer coordination evolution in large software projects.

Findings

Developers form scale-free networks with few highly connected individuals.

Coordination requirements increase with project size but are limited by an upper bound.

Initial hierarchical structures evolve into hybrid forms with core and peripheral developers.

Abstract

Software evolution is a fundamental process that transcends the realm of technical artifacts and permeates the entire organizational structure of a software project. By means of a longitudinal empirical study of 18 large open-source projects, we examine and discuss the evolutionary principles that govern the coordination of developers. By applying a network-analytic approach, we found that the implicit and self-organizing structure of developer coordination is ubiquitously described by non-random organizational principles that defy conventional software-engineering wisdom. In particular, we found that: (a) developers form scale-free networks, in which the majority of coordination requirements arise among an extremely small number of developers, (b) developers tend to accumulate coordination requirements with more and more developers over time, presumably limited by an upper bound, and (c) initially developers are hierarchically arranged, but over time, form a hybrid structure, in which core developers are hierarchically arranged and peripheral developers are not. Our results suggest that the organizational structure of large projects is constrained to evolve towards a state that balances the costs and benefits of developer coordination, and the mechanisms used to achieve this state depend on the project's scale.