TTC 2025

Changed Format

This year, we changed the format of the TTC. The most important changes are the following:

• You can still submit cases and solutions, but from this year, you can also submit new or significantly updated solutions to past cases. For this, we created an Overview page that lists past cases.
• If you submit a solution to an older case, you have to compare your solution with all known existing solutions.
• If you submit a case, you can only expect solution papers in the following edition of the TTC.

Transformations of structured data such as relational data, abstract syntax trees and high-level graph-based models are cross-disciplinary at the heart of a wide range of applications. The success of transformation approaches heavily depends on the availability of expressive and efficient tools. Currently, a large variety of tools exist for different transformation approaches. However, for potential users, working in application domains where transformation techniques may be useful, it is difficult to select the right tool for their purpose. Moreover, even for most of the tool experts it is true that they know about one or two tools but little about others. Finally, the tool developers themselves can also be inspired by a more detailed understanding of related approaches.

The aim of this event is to evaluate and compare the expressiveness, the usability and the performance of transformation tools for structured data along a number of selected challenging case studies. That is, we want to learn about the pros and cons of each tool considering different applications. A deeper understanding of the relative merits of different tool features will help to further improve the existing tools, to indicate open problems, and to integrate and standardize transformation tools.

There is a wide range of application domains of transformation tools, including software engineering, business intelligence, logistics, healthcare and bioinformatics, as well as semantic web and social network analysis. Specific areas of transformations relevant for the TTC include (among others):

• model synchronisation and merging,
• program manipulation and translation,
• interoperability and migration,
• model execution and simulation,
• verification of models and transformations,
• knowledge extraction and semantic search

If you are working in one of these areas or a different domain where structured data transformations are relevant, please consider submitting a case.

Cases and solutions, including those of previous years, are/will be published at the Transformation Tool Contest website.

If you have questions, contact us by email at: ttc25@easychair.org

Call for Solutions

The 2025 Transformation Tool Contest (TTC) seeks your own spins of four interesting model transformation problems. The deadline for solution descriptions is April 7, 2025, immediately followed by a round of open peer reviewing. As in previous editions, solution descriptions will be published in a post-proceedings volume, and lead to continued collaboration for producing a per-case journal article.

About TTC

The aim of this event is to compare the expressiveness, the usability and the performance of graph, model and program transformation tools along a number of selected case studies. A deeper understanding of the relative merits of different tool features will help to further improve transformation tools and to indicate open problems.

This contest is the fifteenth of its kind (after an AGTiVE 2007 session, as GraBaTs 2008 and 2009 contests, and the TTC 2010, 2011, 2013–2021 contests). For the eighth time, the contest is co-located with several leading software engineering conferences as part of the Software Technologies: Applications and Foundations (STAF) federation. Teams from the major international research groups in the development and use of transformation tools are expected to participate in the TTC again.

Participating in the Contest

The following case studies have been selected:

• Program abstraction by transformation: Abstraction of Visual Basic to UML (Resources).

The case description, supporting resources, and discussion between solution developers are hosted at the source code repositories linked to above.

If you would like to participate in the contest, you are now asked to take your favourite transformation tool and submit your solutions. A submission should consist of a paper and the actual solution (i.e., programs, models, etc.). The paper should include a description of the chosen case study variant (if any) and a presentation of the chosen solution, including a discussion of design decisions. Examples can be explored at the TTC 2021 website.

Solutions should be submitted via Easychair by April 7, 2025. Before the same deadline, each case study solution (tool, project files, documentation) should be made available for review and demonstration via a public version control repository (e.g. on Github or Bitbucket). Docker Hub images would be highly appreciated as well.

Immediately after the submission deadline, please note solution developers will be asked to participate in a round of open review of other solutions. Therefore, we ask that all solution developers are available in the following weeks to participate in these discussions.

Publication Procedure

For TTC 2025 there will be several publication

• There will be formal contest proceedings. Solution submitters have to consider and address the opponents’ statements. The resulting solution papers will be reviewed by the TTC program committee. A selection of revised solution papers together with the case descriptions will be published in the contest proceedings.
• Most cases were reviewed by a steering committee, judging the suitable publication venues, significance of the problem statement, and appropriateness of the evaluation methodology. This feedback was passed on to case authors to allow the case to be improved, with the aim to facilitate a thorough comparison of the state-of-the-art in model transformation, which may be submitted to one of the following journals after the workshop:
  • The International Journal on Software and Systems Modeling (SoSyM)
  • The Journal of Object Technology (JOT)
  • The International Journal on Software Tools for Technology Transfer (STTT)

Call for Cases

What is this about?

Transformations of structured data such as relational data, abstract syntax trees, graphs and high-level software models are at the heart of a wide range of applications, including but not limited to the development of low-code platforms. Their success heavily depends on the availability of powerful and easy-to-use tools. There is an increasingly large number of transformation tools that follow many different approaches, and this creates challenges for the community at large. Users and tool experts may have missed a recent development in the area, and they may not use the best tool for the job. Tool developers may wish to compare their tool against others, but risk the threat to validity that they may not be using the other tools to their full extent.

The Transformation Tools Contest aims to help users, experts and tool developers to learn about the state-of-the-art through practical case studies. While some of these case studies may revisit well-known transformations, we are always looking for new case studies from the community that look at the bleeding edge in the field or challenge current tools in some way. If you have an interesting transformation problem in hand, or if you know about one, we would like to hear about it! We mention some specific areas that we consider relevant to TTC in our aims and scope page.

Authors of cases are asked to facilitate a thorough comparison of state-of-the-art transformation tool features for solving a particular problem with the aim of submitting a journal article with qualifying solutions to one of the following journals after the workshop:

• The International Journal on Software and Systems Modeling (SoSyM)
• The Journal of Object Technology (JOT)
• The International Journal on Software Tools for Technology Transfer (STTT)

More information about what to consider in a case can be found below.

Case submission

By April 7, 2025, please submit your case description in PDF format through EasyChair. A previous expression of interest is not a requirement to submit a case but we encourage authors of cases to contact the TTC organizers early. The case description should include a URL to a source code repository (e.g. GitHub, Bitbucket, GitLab) that contains a reference solution and an evaluation methodology, and a basic issue tracker that solution authors may use to ask questions about the case study. For the evaluation methodology, you are welcome to draw from past case studies. If you have an idea for a case study but do not know where to start or which previous case to base it on, feel free to start a discussion with us at ttc25 AT easychair DOT org.

The case description should be in the ACM acmart LaTeX document class (see here and here), using the “sigconf” style and with the “review” option enabled, and not exceeding 10 pages (excluding references and appendices).

The description should answer these questions:

• What is the context of the case?
• What is the subject to be modeled?
• What is the purpose of the subject?
• What are the variation points in the case?
• Are there any specific research questions you would like to answer through the participation of the community? What is the novel aspect of the problem that has not been published earlier?
• What are the criteria for evaluating the submitted solutions to the case? These criteria should include pointers to the sections to be included in the short paper describing the solution.
• What should be the prizes for the case? Usually, there may be one or more “Best X” (where X is a desired attribute), and then a “Best Overall” solution with the best balance between all attributes.
• Correctness test: which are the reference input/ouput documents and how should they be used? Ideally, a case description includes a test suite, as well as a test driver. The test driver can be an online web service, or a Docker image on Docker Hub. You can reuse frameworks from past case studies - feel free to ask us!
• Which transformation tool-related features are important and how can they be classified? (e.g., formal analysis of the transformation program, rule debugging support, …)
• What transformation language-related challenges are important and how can they be classified? (e.g., declarative bidirectionality, declarative change propagation, declarative subgraph copying, cyclic graph support, typing issues, …)
• How to measure the quality of submitted solutions, at the design level? (e.g., measure the number of rules, the conciseness of rules, …)
• How can the solutions be evaluated (ranked) systematically?
• Building on the above, define threshold criteria for solutions to be eligible in the journal article so that PC members can objectively refer qualifying solutions.

Subsequent Phases

Phase 2: Case evaluation. Members of the steering committee comment on cases according to the following survey:

1. Choose the journal (SoSyM, STTT or JOT) that you think fits best this case and briefly justify your view. Is the case within the scope of the journal? Is the problem statement interesting for the audience of the selected journal? (normally up to 100 words)
2. In the questions below, please highlight strengths, potential flaws and constructive ways to improve each aspect:
   1. Please comment on the significance of the problem statement. Are the research questions addressing aspects that are novel and relevant, paving the way either for exploring insights into a new problem or for learning new knowledge about an existing problem? Is the case building on state-of-the art literature in that topic? If not, please suggest relevant references that should be considered. (normally up to 200 words, excluding references)
   2. Please comment on the appropriateness of the evaluation methodology. Does the proposed methodology enable a valid, reliable evaluation of solutions? Please consider the questions below for further guidance. (normally up to 200 words)
      • RE reliability, is the methodology likely to lead to consistent or repeatable measurements?
      • RE validity, is the methodology assessing relevant characteristics of the problem statement (content validity)? To which extent does it help study a trustworthy causal relationship between research questions and measurements (internal validity)? How well does it enable generalizable findings (external validity)?

This feedback is passed on to case authors to improve the case with the assistance of the organization committee.

Phase 3: Call for solutions (next edition of TTC). All those who like to participate in the contest will be asked to choose one or more case studies, take their favorite transformation tool and submit their solutions. A separate call for solutions will be distributed in the next TTC edition, after the cases have been selected. A solution consists both of a technical short paper describing the solution and of accompanying software artifacts in a Git repository (usually a clone of the repository provided for the case). For a solution to be eligible for an award, it must not contain any member of either the Organization Committee or the Steering Committee. However, members of the Organization Committee and of the Steering Committee are welcome to contribute solutions, which will undergo the rest of the contest stages below together with the other solutions.

Phase 4: Open peer review. The solution reviewing before the workshop will be done by other solution submitters. All solution submitters have to review three other solutions to the case that they have addressed. These reviews will not be anonymous, since these reviewers ideally will also be the opponents at the workshop. The purpose of the peer reviewing is that the participants get as much insight into the competitor’s solutions as possible and also to raise potential problems. Case submitters should be available at this stage to resolve conflicting interpretations (if any) about the case description.

Phase 5: Proceedings. Solution proponents improve the short paper with the feedback received during the open peer reviews. Such papers will be reviewed by programme committee members selecting which solutions are eligible for the journal article of each case, according to the corresponding eligilibility criteria. All papers, including cases and solutions, will appear in the proceedings.

Phase 6: Contest. The solutions submitted for each case will be presented by their proponents. Case submitters should have evaluated independently the various presented solutions and should be present during the break to discuss the final awards to be given. Awards are only given for cases submitted to the last edition of the TTC. For more details (such as example cases and solutions from previous editions), please consult the other sections of the TTC website.

Phase 7: Journal article. Case authors prepare journal articles with eligible solutions.

Call for Extensions

The 2025 Transformation Tool Contest (TTC) seeks your own spins of four interesting model transformation problems. The deadline for solution descriptions is April 7, 2025, immediately followed by a round of open peer reviewing. As in previous editions, solution descriptions will be published in a post-proceedings volume, and lead to continued collaboration for producing a per-case journal article.

About TTC

The aim of this event is to compare the expressiveness, the usability and the performance of graph, model and program transformation tools along a number of selected case studies. A deeper understanding of the relative merits of different tool features will help to further improve transformation tools and to indicate open problems.

This contest is the fifteenth of its kind (after an AGTiVE 2007 session, as GraBaTs 2008 and 2009 contests, and the TTC 2010, 2011, 2013–2021 contests). For the eighth time, the contest is co-located with several leading software engineering conferences as part of the Software Technologies: Applications and Foundations (STAF) federation. Teams from the major international research groups in the development and use of transformation tools are expected to participate in the TTC again.

Solutions to older cases

Transformation tools have evolved and continue to evolve, but use cases of the past are still relevant. To foster a culture of community-accepted benchmarks, the TTC now also accepts submissions that solve older cases. References to prior cases can be found here. Please note that for solutions to these prior cases, we expect solution authors to compare their solutions with other existing solutions.

Submissions of solutions to past cases will undergo the same peer-review process as solutions to the selected case from the past year. We will try to have the solution submission reviewed by of the original case authors or original solution authors.

Solutions should be submitted via Easychair by April 7, 2025. Before the same deadline, each case study solution (tool, project files, documentation) should be made available for review and demonstration via a public version control repository (e.g. on Github or Bitbucket). Docker Hub images would be highly appreciated as well.

Publication Procedure

For TTC 2025 there will be several publication opportunities:

• There will be formal contest proceedings. Solution submitters have to consider and address the opponents’ statements. The resulting solution papers will be reviewed by the TTC program committee. A selection of revised solution papers together with the case descriptions will be published in the contest proceedings.
• New solutions or significant improvements to existing solutions may also lead to new joint (journal) papers for the case, especially if such a paper was not successful due to an unsufficient amount of solutions in the past.