Joining the Symfony AI Core Team

By Johannes Wachter, Sulu core developer and contributor to symfony/ai. A personal note on being asked to join the new Symfony AI Core Team.

A few days ago Chris Hertel asked me if I wanted to join the new Symfony AI Core Team, and I had to read the message twice before it sank in. The other names on the list were Fabien Potencier and Oskar Stark.

I could not be happier. The last months have been intense: building Mate, pushing tools upstream, going back and forth on pull requests until they were right. Seeing that work recognised at this level is more than I expected, and a reward in itself.

I have looked up to names like that since I was new to Sulu, PHP and Symfony: Bernhard Schussek, Nicolas Grekas, Fabien Potencier, Kévin Dunglas, Tobias Nyholm, Jordi Boggiano and Nils Adermann, the creators of Composer, and plenty of others whose commits and talks taught me how this ecosystem actually works, long before I understood it well enough to contribute to it myself. Without them, the framework and the community around it would not be the same.

Ryan Weaver belongs among them too. He passed away in 2025, and the community still feels the loss of one of its biggest figures, a teacher as much as a core team member.

Not all of them carry the title Symfony core developer, but all of them share the same willingness to build in public and carry open-source projects forward. I’m now a Symfony core developer myself, in the AI team. The title puts me on the same level, but it does not give me the same history or standing they have earned over the years. And now my name sits next to theirs, and that feels surreal.

Where this comes from

I’m a core developer at Sulu, and on my own time I built Symfony Mate, the agentic tool that gives coding agents runtime access to a Symfony application instead of making them guess from source code alone. I also built Modelflow-AI, a provider-agnostic AI framework I started before symfony/ai existed and have more or less abandoned since. I still maintain a few other libraries that are widely used.

That is the work behind the invitation. Knowing that still does not make it feel entirely real. Fabien is everywhere in the framework itself. His name is on source files across it. He is the one on stage, talking about where it goes, often the one turning a direction into momentum, taking the initiative and shaping the team that carries it forward. Chris has driven more of symfony/ai than anyone. He is also the one I go to when an architectural decision needs settling, and usually the first to turn that decision into working code. Oskar was shaping Symfony’s conventions long before AI became part of the project.

Over the years I have crossed paths with all three in different ways: through reviews, discussions, pull requests that went back and forth more than once, and conversations at conferences. Sulu has been part of that too, sponsoring Symfony, showing up at conference after conference, and giving back where we could to a framework we have benefited from for years. I have learned something from every one of them. And now I’m closer to the decisions and discussions that shape where this part of Symfony goes next.

Something forming

Looking back at the last few months, something had already been taking shape: a team that cares where Symfony AI goes, takes initiative instead of waiting to be told, and takes responsibility for what follows. Chris, Oskar and I were already doing that. Now Fabien is formally part of it too. I want to keep doing exactly that, and I’m looking forward to what comes next.

Why I’m writing this down

I don’t usually write about myself here. But I wanted this on the record in my own words: joining this team means I get to call myself a Symfony core developer, next to people I have looked up to since I was starting out. That is not a small thing, and I would rather say so plainly than let an announcement gloss over it.