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REUSE goes to space!


The German Aerospace Center (DLR) has adopted the REUSE specification in some of its projects. We have talked to Tobias Schlauch, research software engineer at the DLR, about the role of Free Software for research and innovation, and the importance of clear understanding and displaying of the legal information of software projects. He highlights the special contributions that REUSE has to offer for software development but also for research.

Image showing the planet Earth from the space

The REUSE initiative, started by the Free Software Foundation Europe (FSFE), makes licensing easy for humans and machines alike. With REUSE, we solve a fundamental issue that Free Software licensing has at the very source: what license is a file licensed under, and who owns the copyright? A set of best practices and the helper tool make the task of adding this legal information in every single file of the project a simple practice.

The number of projects implementing REUSE in their workflows is steadily increasing. This is the case for some projects of the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt e.V - DLR), which are now REUSE compliant. To learn more about the state of Free Software at the DLR, the implementation of the FSFE’s REUSE, and how research and software freedom intertwine, we interviewed Tobias Schlauch.

Tobias is a research software engineer at the Institute for Software Technology at DLR since 2005. He currently serves as the representative of the DLR Software Engineering Initiative. In this position, he organises the DLR research software community and coordinates the DLR-wide application of software engineering methods, processes, and tools.

FSFE: Welcome Tobias, and thank you for taking the time to let us know more about the work carried out by DLR, especially when it comes to Free Software and a proper licensing and copyright displaying of such projects. Let’s start from the beginning: why is software a core activity of the research carried out by DLR?

Tobias Schlauch: DLR is a large research organization in Germany with more than 10,000 employees which are organized in 54 research institutes and facilities. Aeronautics, space, energy, transport, and digitalisation are currently its main research domains. Software development plays an important role in all of them and is a driver of innovation.

Overall, you can find a wide variety of developed software at DLR in terms of application domain and required maturity level. For example, software is developed to help investigating specific phenomena such as simulation of air flow around flight configurations. Another typical use case is the processing, analysis and visualization of scientific data. Moreover, there are also teams developing software for critical space missions such as control software of satellites.

Image of Tobias Schlauch

FSFE: What role does Free Software play within the research ecosystem at DLR? And what do you think are the benefits that Free Software offers to such a community?

Tobias Schlauch: Free Software is an important basis for DLR’s software development efforts. There is likely no software project which does not rely on at least one Free Software library or uses a Free Software tool to aid in the process of software development. Thus, Free Software helps us to rapidly try out new things because we do not have to develop them from scratch. Besides these more efficiency-related aspects, publishing Free Software in the research domain helps to exchange knowledge inside a research community and between different research communities. In this way, Free Software can be a driver for innovation in research.

"Free Software is an important basis for DLR’s software development efforts. There is likely no software project which does not rely on at least one Free Software library or uses a Free Software tool to aid in the process of software development".

FSFE: In research, reusability is at the heart of the scientific process, yet it is still one of the challenges in software development research. Why do you think this is an issue at the moment, and what kind of measures is DLR taking to tackle it? How can a tool like REUSE help with these efforts?

Tobias Schlauch: The use and reuse of software in research has its specific challenges. Generally, a core aspect of research is that you can validate and build upon the results of other research groups. For example, you want to be able to take the “ingredients” described in a scientific paper, such as data sets and software, and get to the same results as the authors of the paper. This kind of validation and reproduction of scientific results is a core aspect of research. However, reproducibility has become more and more challenging with the rise of computational research and has led to the so-called reproducibility crisis. For example, still too often it is not clear which concrete software version has been used to achieve a specific result or, even worse, the used data sets and software are not available at all.

The movement towards Open Science tries to address this problem by establishing principles and practices to make research products such as software openly available. In this context, the FAIR principles provide guidance how to share research products to enable reuse and reproducibility. Initially, the Open Science community focused a lot on data but nowadays also software has been more and more established as a research product. Thus, there is also an interpretation of the FAIR principles for software.

An important aspect of code reuse is that you have a clear understanding about the licenses under which code is provided. In this context, REUSE makes a unique contribution by providing a practical standard for documenting such information in a code repository while not reinventing the wheel. In particular, REUSE addresses the problem of multiple licenses and different copyright holders as it allows to precisely express such information on a per-file level. Finally, REUSE offers really good tool support which helps during the initial documentation phase and the further development by offering a linting functionality.

At DLR, we need to transfer these Open Science related practices into the DLR context. This requires DLR-specific policies and support activities to effectively enable our researchers to publish research openly. The DLR software engineering initiative provides this practical support in context of software development. I.e., we foster the establishment of required tool infrastructure, offer guidelines, training and consulting. For example, in context of software publication, we offer a help desk which DLR researchers can approach to ask questions with regard to Free Software and software licenses. In addition, we also provide Free Software guidelines to answer common questions with regard to these topics.

FSFE: The DLR project - CosmoScout VR - has recently implemented the REUSE specification. How did they arrive at that decision?

Tobias Schlauch: I approached them with the idea and I did not have to be too convincing. They already recognized the point that one single license for the whole repository does not feel right. REUSE allows them to be precise and to make sure that they do not accidentally miss an important aspect.

FSFE: Do you see the potential of more DLR projects joining CosmoScout VR in becoming REUSE compliant?

Tobias Schlauch: Yes, I think so. Actually, there are already much more compliant code repositories out there. But they do not necessarily use the current REUSE badge feature. For example, we also provide our learning materials in Git repositories which we made REUSE compliant. In addition, in the DLR institute I work for, the Institute for Software Technology, we currently rebuild our software publication process and REUSE is to become a standard tool in it. However, I think that there is more room for adoption of REUSE on the wider DLR level.

“An approach such as REUSE makes it much easier to follow an established good practice… I do not have to think where to put a specific information such as the license files as REUSE gives me clear advice. In addition, REUSE helps me to check whether I accidentally missed something. Such tools are really, really important because they bring a standard into practice.”

FSFE: One of your efforts within DLR has been educating and guiding the DLR research software development community on how to properly declare licensing and copyright information for their work. What would you say to someone working in this field to encourage them to use Free Software?

Tobias Schlauch: I think that many researchers at DLR are already aware of Free Software and their benefits. However, another part of our educational efforts is to ensure that they are using them the “right” way. Thus, license compliance is an important aspect here which also starts with raising awareness. For example, by providing researchers small rules of thumb such as “Make sure that the code you want to reuse has a clear license.” or “Make the license a decision criterion when selecting a Free Software library”. In addition, we also encourage our researchers to publish their own developments as Free Software or, even better, contribute to existing Free Software projects. In this area, there is still room for improvement but we try to encourage them by pointing out the benefits of open collaboration such as improved visibility, sustainability, and quality of published software. Finally, when making your developed research software available as Free Software, you also ensure that your work is still available to you and the wider research community after your contracts end and you head over to another research organization.

FSFE: Are tools like REUSE key to educate and guide the rest of the research software development community?

Tobias Schlauch: Yes, I think so. An approach such as REUSE makes it much easier to follow an established good practice. For example, I do not have to think where to put a specific information such as the license files as REUSE gives me clear advice. In addition, REUSE helps me to check whether I accidentally missed something. Such tools are really, really important because they bring a standard into practice.

FSFE: Indeed, DLR is not only adopting REUSE but also has included it as a reference within its Free Software guidelines. Is the DLR aiming to including REUSE into its licensing policy as well? How do you think this would benefit DLR and the research ecosystem as a whole?

Tobias Schlauch: Yes, I think that REUSE has a good chance to be included in our DLR policies with regard to software publication. There are different activities planned, for example, in context of the adoption of the Model Policy on Sustainable Software at the Helmholtz Centers at DLR. In close relation to this, we might already earlier update the DLR Software Engineering Guidelines and make REUSE the default way on how to document license and copyright information. The effect in the wider research community will take some time but I think that we can reach a point where we finally have a clearer picture of the license situation when reusing software.

FSFE: If you could improve/change something to bring the Free Software ecosystem and the research community closer together, what would that be?

Tobias Schlauch: I would like to remove the fear of researchers publishing their code as Free Software and to encourage them to contribute to existing Free Software projects more often.

FSFE: Once again thank you very much, Tobias, for your insights and for all the efforts you are leading within the DLR and the research community.

Thanks to all our volunteers, contributors, and supporters!

It is always a great opportunity to thank our volunteers and external contributors to REUSE for their great work in continuing improving the tool and documentation but also for keeping up an ongoing and fruitful discussion regarding its specification.

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