Measuring and Understanding the Effectiveness of JIRA Developers Communities Tools for project management and issues/bugs tracking are becoming useful for governing the development process of Open Source software. Such tools simplify the communications process among developers and ensure the scalability of a project. The more information developers are able to exchange, the clearer are the goals, and the higher is the number of developers keen on joining and actively collaborating on a project. In this paper we present a preliminary empirical analysis of the communities-structure of developers in JIRA by analyzing 7 popular projects hosted in the repository. We analyze how these communities perform in terms of issue-resolution time of any given issue. The main contributions of this work are the confirmation of the existence of communities in developer networks, and the empirical finding that the issue resolution-time of any given issue is not correlated with the dimension of a developer community.