Last Updated on 3. June 2026
At the end of May 2026, mgm technology partners made its A12 development platform open source – a move that has attracted attention within the industry. For years, A12 has been at the heart of complex software projects for clients in the public sector and the private sector. In this interview, Sergio Lerena, a member of mgm’s management board, explains the reasoning behind this decision, what the preparations involved – and what he hopes for the future of A12.
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Interview: Sergio Lerena, Member of the Executive Board, Public Sector, mgm
Moderation: Nadine Kneschke, Content Marketing Manager, mgm
Length: 22 Minutes
Key points at a glance
What is A12? A12 is mgm’s enterprise development platform – a low-code platform that enables model-based software engineering at an enterprise level. The best-known example is Elster, the largest ecosystem in the German tax administration. Why open source now? This move is the result of a lengthy process. The growing need for digital sovereignty – particularly in the public sector – has driven the decision. Since the end of May 2026, A12 has been available on GitHub and openCode under the European EUPL licence. What was the biggest challenge? Third-party licences had to be reviewed, documentation revised and support models developed. Real risks relating to licensing and competition were minimised through systematic programme management. Who benefits from this? Primarily public administration – from ministries to local authorities. But also other sectors such as industrial insurance and IT service providers who wish to build on A12 in the future. What’s next? External contributions are not yet possible – mgm is first establishing the necessary community infrastructure. Success will be measured by the growth of the partner network, expansion into new sectors, and the demonstration that open source and enterprise-level capabilities are not mutually exclusive.
The full interview
Nadine Kneschke: Hello Sergio, it’s great that you’ve found the time today.
Sergio Lerena: Hello Nadine, thank you very much for having me here today.
Nadine Kneschke: Before we get into the topic, I’d suggest you introduce yourself briefly. What is your role at mgm and how long have you been with the company?
Sergio Lerena: I’d be happy to. My name is Sergio Lerena. The name might sound Spanish to you, as I was born in Madrid. I’m a business IT specialist and have been in Germany since 1999. I’ve been with mgm for over 20 years. And during that time, I’ve had the chance to take on many different roles – from Java developer to technical lead in development and quality assurance, right through to overall project manager. And since the end of 2020, I’ve been a member of the management board at mgm.
Nadine Kneschke: So why don’t you just describe it straight away: what is A12 and how would you explain it to someone who’s never heard of it?
Sergio Lerena: A12 is best explained by looking at the history of mgm. From the very beginning, we specialised in the development of enterprise applications, and over the years we have built up a team of skilled engineers who successfully bring projects into production. What we observed was that projects were working in isolation from one another and therefore weren’t benefiting from each other’s experience. We had left a major lever for efficiency untapped here. And the solution was ultimately to develop shared components across projects. It’s important to know that A12 stands for ‘Alliance 2012’. That was the first year in which several projects came together to develop across project boundaries. And the A12 platform emerged from this alliance.
A12 is based on model-driven software engineering. That is why we categorise it as a low-code platform, but at an enterprise level. The platform enables business experts and technically-minded staff to implement their business logic in the form of models without delving deeply into the complex world of programming. And this separation between business expertise and technology is a huge lever in practice. So, to summarise: A12 is an open platform for the model-based development of business-critical applications, including professional bespoke software development, AI support, and system integration.
Nadine Kneschke: Do you have a specific example for us?
Sergio Lerena: The best-known example is Elster, the largest ecosystem in the tax administration, which many people undoubtedly use every year. The specific low-code approach at Elster means that tax experts in the tax administration build the entire business process chain digitally. In other words, using the development environment we provide for them, we implement their tax logic in models. These models are used for a wide variety of purposes – for designing forms, validating inputs, performing calculations, and also for mapping data. A typical example would be transferring data from a Riester pension certificate into the income tax form. To do this, the data is transformed and mapped.
What makes A12 so special is that the platform is designed to be open. This means it allows technicians to customise the platform to suit their specific project needs. And the figures speak for themselves: projects built on A12 now account for around 60 to 70 per cent of our turnover.
Nadine Kneschke: And now you’ve made A12 open source. What was the deciding factor?
Sergio Lerena: It was a gradual process. It wasn’t a single moment, but rather growing pressure from various quarters. A12 is widely used in the public sector, where the call for digital sovereignty and the use of open-source software has been steadily increasing. Digital sovereignty is no longer just a trend; given the current geopolitical situation, it has become a genuine question of a state’s ability to act.
We deliberately developed A12 based on open standards from the very beginning. And about a year and a half ago, we decided to make the platform itself open source. A12 has now been publicly available since the end of May 2026 – both on openCode, the central open-source platform for the German public administration, and on GitHub.
Nadine Kneschke: We’re curious to see how this goes. What do you expect to gain from this, both strategically and culturally?
Sergio Lerena: Strategically, I see two main things. Firstly, barriers are being removed. In the past, there were projects and public authorities that would have liked to use A12, but where proprietary software was politically difficult – and that has now changed. And secondly, new doors are opening, for example with digital initiatives by ministries that are building digital, sovereign ecosystems.
And on the cultural side: our colleagues at mgm have been using open-source software themselves for years, and now, with A12, we can give something back – which naturally makes them proud.
Nadine Kneschke: I see. But with such large projects and decisions, there are surely also dissenting voices or concerns. How did you deal with that?
Sergio Lerena: Oh yes, the decision wasn’t an easy one for us, because there are, of course, real risks involved in making such a complex and mature platform public. For example, issues surrounding licensing or how to deal with competition. That’s why, right from the start, we set up a programme management team to systematically identify these risks and develop concrete measures to minimise them. And in the end, it was clear: the opportunities far outweigh the risks, and that is why we made the open-source decision.
Nadine Kneschke: There must be a lot of preparation involved in making an established enterprise stack like A12 open source. Can you explain what is required for that?
Sergio Lerena: Oh yes, it really is a lot of work. More than one might assume from the outside. First of all, we have to review all third-party licences and ensure that they are compatible with the EUPL licence we have chosen. This is a European open-source licence that fits our context very well, particularly in the public sector. Then we had to tackle the documentation. A clear distinction must be made between community features and commercially licensed add-on components. And finally, we developed support models that we offer alongside the platform. All of this has to be right before we open-source the platform.
Nadine Kneschke: We’ve already touched on the fact that there were internal concerns too. How did you get the development teams on board?
Sergio Lerena: We had the developers’ support right from the start, because our mgmies are proud that we’re taking this step. As far as the technical side is concerned, we already have a very solid foundation, and the core of A12 has always been available to our customers as open source. This means that the step we’re taking now simply gives the source code greater visibility. The development teams can now see the logic behind this. For them, it’s a further step forward, not a leap into the unknown.
Nadine Kneschke: That sounds good. You’ve already touched on this: the technical perspective and the technical side of things. What makes A12 so special in that regard?
Sergio Lerena: We’re already familiar with the core principle: subject matter experts can implement validation rules, business logic and so on themselves – without developers and without code changes. What makes A12 special is that this works at a genuine enterprise level. In football terms, you’d say: A12 plays in the Low Code Champions League. And what makes A12 special beyond that – the platform has evolved over decades in highly critical production environments. It’s important to note that the average lifespan of our systems is over 10 years, and aspects such as security, compliance and accessibility aren’t afterthoughts, but are built into the platform from the outset. Furthermore, the open architecture allows us to integrate more and more AI projects into the platform.
Nadine Kneschke: We’ve already talked about large enterprise projects. That means we have a lot of code that we’re releasing. You’ve decided not to accept contributions to start with. Was that a conscious decision, and can you explain exactly what’s behind it?
Sergio Lerena: That’s an important question. With A12, we are making a mature and large platform open source, and accordingly we expect there to be a significant response from the community. This means we need to prepare for numerous requests for contributions, and that requires us to set up a suitable team on our side so that we can handle such requests professionally. And that is why we have made a conscious decision not to accept contributions initially, until we have established this suitable organisation.
And, by the way, this is not an unusual approach. In the past, some large software projects have also made the product available in read-only mode when launching their open-source initiative.
Nadine Kneschke: Let’s move on to another point. Who are you aiming to reach with the open-source initiative, and what do users gain from it?
Sergio Lerena: A primary target group is, of course, still the public sector – that is, government bodies, institutions, etc. – which require long-lasting software and are also committed to digital sovereignty. And now that the barrier of proprietary licences has fallen, we naturally hope to see it adopted in other federal states, ministries, local authorities, etc. A concrete example: In Schleswig-Holstein, we are supporting the administration in migrating Access applications to the sovereign A12 platform. And A12 is by no means just a matter for public administration. Other sectors are also benefiting, such as industrial insurance, where customers have been working successfully with A12 for many years.
Other sectors will certainly follow, those that require sovereign and secure handling of their data whilst seeking an efficient platform for their digital processes. And ultimately, IT service providers who implement applications or even entire application landscapes for their clients. They can build on A12.
At this point, I’d like to clear up a misconception: A12 isn’t just intended for implementing forms. It isn’t a forms server, but a platform that enables true end-to-end digitalisation. That means everything from online applications to case-handling processes – and all of it supported by AI.
Nadine Kneschke: Thank you very much, Sergio, for that. If we were to fast-forward a little to the year 2028, for example, how would you know that the decision to make A12 open source was the right one?
Sergio Lerena: For me, there are three indicators by which I would measure success.
• Firstly: the growth of our partner network. We have been building an A12 partner programme for more than four years. This includes companies that act as solution partners and independently develop bespoke A12 applications, as well as technology partners whose software products are integrated into A12 solutions. And if this network grows as a result of the open-source release, that is a clear sign of success.
• Secondly: the number of local authorities, government bodies, etc., using A12 is also growing – as is the number of players in sectors outside the public sector.
• And thirdly – and this is the most important thing for me: that we will then have proven that A12 continues to function at an enterprise level as an open-source platform. This means: digital sovereignty is no longer just a buzzword, but something you can download, get your hands on and put to use.
Nadine Kneschke: Well then, I’ll keep my fingers crossed that you’ve made the right decision and that A12 will soon be used in further public administration projects or even in other sectors. And perhaps to wrap up for today, what is your personal wish for the open-source project?
Sergio Lerena: My wish is that A12 finds a society that not only demands open-source-based digital solutions, but also procures them accordingly. There have been some positive examples in the past, but also some that are not so encouraging. I’m thinking of a specialist article about a position paper by the Open Source Business Alliance (OSBA), which advocates for the sustainable procurement of open-source software. It highlights the benefits of close collaboration between a contractor and the manufacturer of the open-source software being used. This gives the contractor direct access to the manufacturer, resulting in better technical support and access to the latest software updates. And anyone of us who has been responsible for software in production knows how crucial it is that problems are resolved quickly, thereby ensuring operational reliability.
And ultimately, I hope we can avoid a situation where services are offered at rock-bottom prices without involving the open-source manufacturer as a partner for further development, maintenance or support. Because let’s not kid ourselves: after a short time, this becomes a lose-lose-lose situation. Why three times? Because the losers in this situation are the client, the contractor and also the open-source software vendor. That is why I hope that A12 will demonstrate that Germany and Europe are capable of building independent digital infrastructure of the highest standard.
Nadine Kneschke: Thank you very much, Sergio, for this comprehensive insight into A12 and the open-source circuit. Thank you for your time, and I’m looking forward to hearing what A12 has to say in the coming weeks, months and years.
Sergio Lerena: Great, Nadine, thank you very much for the excellent interview. I’m already looking forward to the next interview with you.
Further information:
Press release: A12 AI Low Code Platform is open source
Press release: A12 Enterprise AI Low Code Platform Goes Open Source: Bavarian State Office for Taxation and mgm Open Up Source Code
