OCTOBER 16th, 2025
BRAID’S TEAM
<aside> 💡 Welcome to another article in our series of Tech Team Profiles! Here, we’ll introduce you to the team building Braid’s automated engineering design technology. Lelio is a Software Engineer at Braid with a background in computer science and aerospace engineering.
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My background is in Aerospace Engineering, specialized in software development for aerospace. During a brief stint as a C++ developer, a friend told me about a computer science Master’s program in Paris. At the time I didn’t even know what computer science really was, since in French “informatique” refers to both software development and computer science. Reading the program description, I realized there was a whole world of things I had never seen before, so I joined.
I then had the opportunity to do a PhD in Paris and became a researcher. I did several postdocs in France during the Covid era before I was able to go abroad. I found a position in Tokyo and moved there, staying three years at a research center. My research started in verified compilation and programming language semantics, then later shifted toward cybersecurity, applying formal methods and verification to network protocols.
The dissertation was about programming languages used to describe control/command software. Model-based design engineers use graphical tools to specify and develop control/command software that will run in a loop on embedded systems. Because some of these applications are critical – for example, power plants and automated trains – the insurance on the code being correct and behaving as expected is very high stakes. Therefore, the code generator that produces sequential code from those high-level graphical specifications must be trusted.
My dissertation focused on formally describing a previously undefined language feature called “reset” and, more importantly, on the mechanized verification of compilers. Instead of relying on testing and certification alone, I developed a mathematically proven end-to-end compiler that translates control/command specifications from a textual programming language into executable code while preserving the intended semantics—for example, ensuring that “3 + 4” never becomes “3 × 4.” This approach, now gaining traction in industry with applications in safety-critical systems such as those at Airbus, provides the highest level of assurance that no bugs are introduced during compilation.
I first got a computer at home in the early 2000s. I became a geek quickly, experimenting with calculators and discovering you could download games like Snake onto them. That made me curious about programming. I started with BASIC on calculators, then moved on to C++ books around age 15.
Later, in engineering school, I studied math and physics intensely, then learned some programming related to engineering tasks, like Fortran and C. I was mostly self-taught in C++, but I didn’t really understand the deeper theory of programming languages until I entered the computer science Master’s. That path eventually led me into logic, proofs, and compiler verification during my PhD.
When I moved to Tokyo, I already knew about Japan’s rugby scene and joined a team right away. I deliberately chose one that wasn’t all French, since I didn’t want to stay within just that community. It turned out to be a great decision—most of my friends in Tokyo now come from the team, and through it I’ve met people from all over the world.
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Lelio playing rugby with his team in Tokyo.
I originally went into research because my first engineering job was both boring and unpleasant. Academia felt more open and less hierarchical. But after years in research, I started to get bored and lose motivation, even after moving to Japan. I wanted to change but found it hard, since people in industry often didn’t understand my academic background.
Then I learned about Braid. I was impressed to find a company where many people also came from academia, so they understood my background. The work sounded exciting, the people were open to research, and the culture felt like a good fit. I was convinced right away during my first interviews.