Internship report Florian

“PDF Tools AG makes the transition into the business IT world a very pleasant experience – professional guidance and support enable a quick entry and fast progress.”

Florian, computer science student, ETH Zurich


Anyone who is interested in developing software within a big project can greatly benefit from an internship at PDF Tools AG. The friendly and helpful atmosphere is very encouraging, and enables great development of skills.

I can highly recommend this internship to fellow computer science students who want to acquire an insight into the professional world of development.

During my internship I have gained a lot of experience and am confident that many of the skills I have developed will help me far into the future.


Who am I and why did I want to do an internship?

I’m a 24 year old computer science student at ETH Zurich. With only few credits left to finish my bachelor’s degree, I decided to use this time to gain hands-on industry experience by doing an internship at a software company.

In ETH’s computer science courses programming is obviously important, however often only as a means to an end – namely to complete the project expeditiously, with few quality requirements other than the code being functional and fast. Many assignments require the creation of rather small blocks of code, which exploit some features of a specific problem to solve it. Although interesting, I knew that this was not a very good representation of real-world programming, especially of large projects. I think these two forms of programming involve two separate skillsets. Since proficiency in both is very important, I wanted to gain additional industry experience.

How did I find PDF Tools AG? Why did I choose PDF Tools AG?

The first time I heard about PDF Tools AG was from a friend who completed an internship with PDF Tools AG. He had been happy here and frequently talked about his experience. When I decided to do an internship, I researched possibilities on our student association’s website. On their Job Board, I found an internship listing by PDF Tools AG, which immediately reminded me of my friend’s experience. Matching the job description, I decided to give it a shot.

How did I secure the internship?

The Job listing listed the email address of Dr. Hans Bärfuss, the founder and CEO of PDF Tools AG. I sent my resume to him and soon received a reply along with an invitation to an interview. The interview itself was a pleasant experience. I was asked about my programming experience and my expectation of the internship and was given more information about the company and what to expect during an internship at PDF Tools AG. I was very happy when I was offered the internship.

What does a day in the life of an intern look like?

At PDF Tools AG an intern is treated very similarly to a regular employee. The main difference was that I had a mentor who introduced me to PDF, the company’s codebase, helped me when I got stuck, and reviewed my code. After familiarizing myself with the relevant parts of PDF, I was assigned a project that I worked on for the main part of my internship. I was included in all the group meetings, which also gave me interesting and valuable insight into the company as a whole. Usually most developers went to lunch together, which was always a good time and facilitated my integration into the team. In general the work atmosphere was very good: people were always friendly, helpful and also very motivated.

What did I learn during my internship?

PDF Tools AG has a very big codebase. I had never programmed in such an environment, so this was new to me. I’ve learned how to explore and deal with such a system and of course I’ve gotten a lot of programming experience. I’ve also learned about good design and coding style, which are key in such a system, as it can otherwise quickly become very hard to navigate and make changes.

I’ve also learned a lot about the portable document format. As a student, I’d had frequent contact with PDF documents, but I’d only displayed them in a reader or generated them using LaTeX, I had never looked at them from a developer’s perspective. Having been around for a long time and building on technologies that have been around even longer, this format considers so many things that one wouldn’t think of naturally when considering what a document format should be capable of. These things are very interesting to learn, and I’ve been surprised many times at the sometimes simple solutions to seemingly complex problems, and sometimes at the complexity of problems that may appear simple at first sight.

The internship with PDF Tools AG gave me a unique glimpse into the daily life at a software company. I faced many new challenges and learned how to overcome them.

Personal highlight

My highlight during the internship was the first time I committed my code. I had been working on my project for quite a while. I hadn’t added it to the company’s code, because as a partially completed unit it wouldn’t have been useful at that point. So when I reached my first milestone there were a lot of changes. Knowing that this code would be deployed to many customers left me feeling excited and proud.

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