23 maart 2021

Lennart Pruijssers: 'I work on the edge of what is technically possible'

Wafer case lennart klein formaat

Lennart has been working for ENTER for about a year now. Once, he started at VMBO T in the direction of Electrical Engineering and then he worked in construction for a while, but that didn't suit him very well. He preferred to work as a system administrator. When he had seen it all, he started programming and scripting. To develop his skills further, he decided to study Technical Computer Science at the Rotterdam University of Applied Sciences. "For my later career choice, Electrical Engineering was pretty useless. But: I can create an electrical circuit in the fuse box, which is also useful," he says with a laugh.

All the different steps he took did help and motivate him tremendously. "If I had gone to hbo or wo in one go, I wouldn't have been able to do everything I do now." Lennart completed his studies with a graduation internship at KPN. He was asked to stay there, but after a while it started to itch again and he went to work at Telfort. There he was mainly involved in programming, but later he was given an additional role as an automation expert. He had to link everything together. Lennart: "I liked that, that's what I wanted to continue doing."

Lennart Pruijssers

Continuing to learn, developing and spreading his wings. It suits Lennart. That's why he went to China for a one-year internship during his studies. Not an obvious choice, but an enormous adventure. He worked at the Chinese bank. It was hard work, but also very interesting. And not only because of the different culture. Lennart: "Living and working in a country where you sometimes get 'lost in translation' can be very strange. People hardly spoke any English and sometimes I had no idea what to do. Fortunately, two other expats on my team were fluent in Chinese and one Chinese team member spoke English, so we still managed to get along quite well. But when you had programmed something, feedback was given in Chinese. In that case I had to check Google Translate to find out what it said."


Once graduated and a few work experiences in the pocket, Lennart started working for a secondment company. Lennart: "I was deployed in a DevOps role more and more. I did both front end and back end development, but also configuration management and automation. There is always plenty of work for developers in general, but if you are also broadly oriented towards IT and have a real passion for the profession, you are wanted even more."

"In addition to programming and improving processes, we are working with mathematics, physics and physics on the edge of what is technically possible. It's really groundbreaking what we do."

Lennart Pruijssers

In that job, Lennart first came into contact with Ian Breedveld from ENTER. "Ian is such a nice guy. I can always call him and have a chat with him." Therefore, it was a logical choice for Lennart to start working at ENTER as well. "At ENTER there is a lot of personal contact. I never feel like a nobody here. Moreover, there was a job for me at TU Delft immediately. I asked Ian: 'When can I start?' And that was right away! With a secondment agency a lot is possible. I have many interests and now I can go in all those directions."

The project at TU Delft was short, but very challenging and educational. Lennart explains: "I worked in an advance research station set up by Tu Delft and TNO, called QuTech. QuTech focuses on the design and realisation of a Quantum supercomputer and the creation of the 'quantum network' so that these supercomputers can communicate with each other and the outside world. There is no standard or existing quantum technology for this, as it is being researched and developed in this very laboratory. The final product will be delivered to IBM and the Dutch government."


Lennart continues: "I worked at a quantum (network) team of four people. This was in collaboration with a group of famous scientists in their fields of expertise of physics, nanotechnology and physics. I really experienced this as an honor and I learned a lot from them". Together with his team, he realized a quantum network. "For example, we made communication possible between two or more quantum supercomputers. We also built a web application on which scientists can perfrom their experiments. This will be accessible for the scientific community later this year. This way, any scientist worldwide can perform experiments on a cluster of supercomputers and interact with qubits of a supercomputer."

Quantum programming or working with qubits was contrary to Lennart's intuition, because he had to program in a completely different way than he did before. Lennart: "A quantum bit can be 1 or 0 at the same time, which means it can be on and off at the same time. It’s a real paradox which is called 'superstate' in technical jargon. The names of me and my colleagues are hidden somewhere in the programming. So should the quantum network/operating system ever become the standard, at least my name will be in it."

Pushing limits

After this very challenging assignment, Lennart started working at ASML as a software developer in a DevOps team. ASML makes microchip machines. Every phone, laptop, computer part or TV on the market probably contains several microchips from this company. ASML's machines create about a dozen wafers a day. A wafer is some kind of round plate or cake with 100 microchips on it, for example 100 processors (CPUs). Lennart: "The connections are so small that even the best electron microscopes can’t zoom in on them. Therefore, in order to test the wafers, physics workarounds must be devised. Our team supports that testing process. We work with developers and scientists on a variety of technical problems. In addition to programming and improving processes, we are working with mathematics, physics and physics on the edge of what is technically possible. It's really groundbreaking what we do."

Lennart and his colleagues brainstorm a lot and solve problems together. "Imagine," says Lennart, "you spend two weeks of thinking about something and working on it and then it works. That's cool, right? Everything is on the edge of what is possible and that is really cool." In between work, Lennart goes for a walk or has virtual coffee hours with his colleagues every now and then. The coffee hours are mainly to catch up on all sorts of things. "I think it's important to work with nice people with whom you can laugh as well. We work very closely together. In order to come to a good solution for a certain problem together, we have to click."