Behind the Code with Patrik Weiskircher

Welcome to “Behind the Code: Stories from PSPDFKit Engineers,” a blog series dedicated to looking at the world of engineering through the eyes of those building the products here at PSPDFKit. In each installment, we’ll sit down with a different engineer to talk about their job and uncover the human side of engineering: what they love, what they find challenging, what makes them tick, and how they shape the future with their work. Whether you’re an aspiring engineer or just curious about how we work at PSPDFKit, join us on this journey to discover the stories behind the code.

Self-Taught Programmer

For the first post, we sat down with Patrik Weiskircher, who is the lead of the Core team at PSPDFKit. Patrik has been with the company for almost 10 years, and he started as an iOS developer before transitioning to working on the core project that powers all of PSPDFKit’s products.

“I just taught myself programming,” Patrik shared of his pre-PSPDFKit background. “I wasn’t very good at paying attention in school, so I spent a lot of time at home programming and playing around with computers.”

He started on Linux, and when iOS was released in 2007, he started dabbling in that as well. This has given him a solid understanding of multiple programming languages.

“I’m good at knowing a little bit of everything,” he said, sharing that he mostly works in C++ with Core, but that he also uses TypeScript, Swift, Objective-C, Kotlin, and other languages as the job requires them. “At some point, when you have enough experience doing this stuff, the language just becomes syntax, and it doesn’t matter too much. Most languages are pretty similar, especially nowadays,” he said, explaining how AI can also be used to help out when you’re working in a variety of languages.

Creating the Core Team

When he first started at the company, Patrik said there were maybe a dozen people working there, all on the iOS product. Eventually, he said, the company decided to branch out to other SDKs, beginning with Android.

“We figured we needed a codebase both iOS and Android could use,” he explained. “So the Core project was created, which is the thing I’ve been working on since then.” Core is what provides the PDF functionality that’s shared between the majority of our products, including the iOS, Android, and Web SDKs, as well as Document Engine.

From Member to Team Lead

In the beginning, Core was a project that people worked on as they were able to. However, as the team grew, it became clear that Patrik was good at what he did, and over time, his role evolved from an individual contributor to more of a team lead — though he describes it as a natural progression rather than a formal transition. “There weren’t really assigned roles for a while — but I seemed to know what I was doing, so I became the team lead.”

Patrik described himself as lucky in his role, because he doesn’t have to spend as much time managing as other team leads might. For example, he categorizes bugs, determines the priority of what his team works on, does performance reviews, and acts as the advocate for his team when collaborating with other teams.

But aside from these managerial duties, Patrik estimated he spends around 95 percent of his time programming. “The Core team is a bit different from the other teams,” he explained. “We’re all very senior engineers working independently on different parts of the company, so I don’t do a ton of traditional team leading — it’s mostly me just working alongside everyone else.”

He also noted that work on Core spans across multiple specialties as opposed to a single product. “The iOS team has a mission: It makes a great iOS framework,” he said. “But on the Core team, we work on everything to keep things running well and to add new features. One person works on digital signatures, another works on generative AI, etc. And while doing all that, we try to fix a few bugs. So it’s not like we work together on things; it’s more like everyone just does something. It’s definitely less team-y than other teams.”

Engineering Culture

Because he’s been at the company for so long, Patrik has a unique experience of having literally seen it grow, and he stressed the importance of new hires speaking up. “Don’t be afraid to share your ideas — everyone here is really receptive to new perspectives, and you can‌ make a difference. It can be scary, but everyone is nice, and everyone values other opinions.”

He also said that anyone at PSPDFKit can make an impact if they want‌ to, noting that a culture of ideation and experimentation is valued here. “Everyone has a voice if they want to have one,” he said. “That’s something that not many companies have in practice, but here, we do.”

Impact at PSPDFKit

As for what he works on, Patrik likened his role to that of a firefighter. “I do so many different things all the time, and my brain is always jumping from task to task,” he said.

However, one of the biggest persistent challenges he faces in his work is that of memory management, as the PSPDFKit SDKs need to work seamlessly on devices that are brand new as well as ones that are 10 years old. “People like to use our stuff on very old devices, so performance and memory optimization is crucial, but also really tricky,” he said.

When it comes to troubleshooting, Patrik relies on his wealth of experience. “I’ve seen a lot over the years, so I usually have at least a gut feeling of where to start looking. Of course, I’m often wrong, but it at least points me in the right direction.”

More than anything, Patrik is proud of the impact PSPDFKit has in the lives of its users. “It turns out many people don’t like to work with documents,” he said. “And I love being able to create things that genuinely make people’s lives easier, even if it’s just by removing little annoyances. Seeing our products out in the world being used is really rewarding. And I just want to do cool stuff that’s useful for our customers.”