Preface Software intensive systems are becoming more complex, driven by the need to integrate across multiple concerns and communicative. Consequently, the devel- opment of such systems requires the integration of many different concerns and skills. These concerns are usually covered by different languages, with specific concepts, technologies and abstraction levels. This multiplication of languages eases the development related to one specific concern but raises language and technology integration problems at the different stages of the software life cycle. In order to reason about the global system, it becomes necessary to explic- itly describe the different kinds of relationships that exist between the different languages used in the development of a complex system. To support effective language integration, there is a pressing need to reify and classify these relation- ships, as well as the language interactions that the relationships enable. In this context, the proposed GEMOC 2015 workshop aims to attract submissions that outline language integration approaches and case studies that identify and dis- cuss well-defined problems about the management of relationships between het- erogeneous modeling languages. The goal is to facilitate deep discussions among the participants that lead to an initial classification of the kinds of language relationships and their management. This volume contains the papers presented at GEMOC 2015: 3rd Interna- tional Workshop on the Globalization of Modeling Languages held on September 27, 2015 in Ottawa. It follows the successful previous two editions at MODELS 2013 in Miami, FL, USA (http://gemoc.org/gemoc2013), and at MODELS 2014 in Valencia, Spain (http://gemoc.org/gemoc2014). This edition complete the state of the art and practice initiated in the previous editions. It also inves- tigates the language interfaces required in the context of the globalization of modeling languages, and the possible relationships with the viewpoint engineer- ing. Finally, it also strengthen the community that broadens the current DSML research focus beyond the development of independent DSMLs to a research focus that provides support for globalized DSMLs. This year, there were 6 submissions. Each submission was reviewed by at least 3, and on the average 3.5, program committee members. The committee decided to accept 3 papers. GEMOC 2015 has been supported by the GEMOC initiative (http://gemoc.org), which promotes research seeking to develop the necessary breakthroughs in soft- ware languages to support global software engineering, i.e., breakthroughs that lead to effective technologies supporting different forms of language integration, including language collaboration, interoperability and composability. October 17, 2015 Benoit Combemale, Julien Deantoni, Jeff Gray v Table of Contents Property-Based Methods for Collaborative Model Development . . . . . . . . . 1 Marsha Chechik, Fabiano Dalpiaz, Csaba Debreceni, Jennifer Horkoff, Istvan Rath, Rick Salay and Daniel Varro Programming against Multi-Version Metamodels: A Model Differencing and Virtualization Approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Robert Bill and Manuel Wimmer Towards a formal semantics of the TESL specification language . . . . . . . . . 14 Hai Nguyen Van, Thibaut Balabonski, Frédéric Boulanger, Safouan Taha, Benoı̂t Valiron, Burkhart Wolff and Lina Ye vi Program Committee Cedric Brun Obeo Marsha Chechik University of Toronto Tony Clark Middlesex University Benoit Combemale IRISA, Université de Rennes 1 Julien Deantoni UNS - I3S - INRIA Sophia Antipolis Mediterranee Jeff Gray University of Alabama Jean-Marc Jézéquel University of Rennes 1 Gabor Karsai Vanderbilt University Ralf Lämmel Universität Koblenz-Landau Marjan Mernik University of Maribor Gunter Mussbacher McGill University Richard Paige University of York Bernhard Rumpe RWTH Aachen University Matthias Schöttle McGill University Mark Van Den Brand Eindhoven University of Technology Eric Van Wyk University of Minnesota Jurgen Vinju Centrum Wiskunde & Informatica Markus Voelter Independent vii