# A large-scale, in-depth analysis of developers' personalities in the Apache ecosystem

## TL;DR

This study analyzes the personalities of Apache developers using ecosystem data, revealing stable personality profiles that influence their behavior and contribution patterns in large-scale distributed projects.

## Contribution

It provides the first large-scale quantitative analysis of developer personalities in open-source projects, identifying common personality profiles and their impact on contributions.

## Key findings

- Three main personality profiles among developers.
- Personality traits remain stable over time.
- Open developers are more likely to contribute.

## Abstract

Context: Large-scale distributed projects are typically the results of collective efforts performed by multiple developers with heterogeneous personalities. Objective: We aim to find evidence that personalities can explain developers' behavior in large scale-distributed projects. For example, the propensity to trust others - a critical factor for the success of global software engineering - has been found to influence positively the result of code reviews in distributed projects. Method: In this paper, we perform a quantitative analysis of ecosystem-level data from the code commits and email messages contributed by the developers working on the Apache Software Foundation (ASF) projects, as representative of large scale-distributed projects. Results: We find that there are three common types of personality profiles among Apache developers, characterized in particular by their level of Agreeableness and Neuroticism. We also confirm that developers' personality is stable over time. Moreover, personality traits do not vary with their role, membership, and extent of contribution to the projects. We also find evidence that more open developers are more likely to make contributors to Apache projects. Conclusion: Overall, our findings reinforce the need for future studies on human factors in software engineering to use psychometric tools to control for differences in developers' personalities.