Ignite Startups: How Open Source and AI Are Transforming Modern Software with Marc Seitz | Ep205

In a world where startups are built faster than ever, access to secure, transparent, and affordable tools has never been more important. Enter Marc Seitz, founder of Papermark, an open-source alternative to DocSend that’s changing how founders share and protect their documents.

From studying physics to leading a global open-source movement, Marc’s journey is anything but linear — and his story reveals how curiosity, experimentation, and community can drive real innovation.

From Physics to Software: The Curiosity-Driven Path

Marc didn’t begin his career in tech. He studied physics, fascinated by the universe and cosmology. But after years of waiting on data from telescopes like Hubble, he realized something was missing — instant feedback.

“In software, you write a line of code and instantly know if it works. In physics, you might wait years for results,” he explained.

That instant gratification, coupled with his growing passion for hackathons, pulled Marc into the world of software development. He began building small tools, joining hackathons across Europe, and eventually turning that spirit of experimentation into a business.

HackerBay and the Power of Rapid Experimentation

Marc’s first company, HackerBay, emerged from those hackathon roots. He and his co-founders saw how talented developers — many of whom were non-traditional or even school dropouts — were building incredible things in short timeframes.

HackerBay partnered with major German manufacturers and enterprises, helping them run rapid “micro-experiments” to test digital ideas before deploying them to production.

“We learned that the first version doesn’t have to be perfect — it just has to deliver value,” Marc shared.

That mentality became the foundation for everything Marc would build next.

The Spark Behind Papermark

After HackerBay, Marc found himself frustrated by the legacy data room and document-sharing tools startups relied on — platforms like DocSend, Intralinks, and others that felt dated, slow, and expensive.

So he asked a simple question: Why isn’t there an open-source version of this?

Over a weekend, Marc tweeted his intent to build one. The post went viral. Within days, thousands of people were following the progress of what became Papermark — a modern, open-source platform for secure document sharing and fundraising.

“Founders told me they hated using DocSend — it was clunky, slow, and lacked innovation. We realized we could build something better, faster, and open to everyone.”

Why Open Source Wins

Papermark’s mission is about more than just convenience. It’s about trust, transparency, and control.

By being open source, any user — from a solo founder to a large bank — can inspect the code, host it privately, and know exactly how their data is handled. This makes Papermark especially appealing to enterprises, governments, and financial institutions that require strong compliance and data sovereignty.

“We don’t need to ask customers to trust us — they can see the code. That transparency accelerates everything,” Marc noted.

Papermark’s dual-licensing model allows enterprises to access additional features under an enterprise license while the open-source community continues to innovate and contribute to the base product.

Managing an Open Source Community

Running an open-source company brings unique challenges. Contributors submit code from all over the world — sometimes brilliant, sometimes chaotic. Marc describes being both founder and product manager at once, carefully balancing community contributions with product direction.

“You have to stay compassionate. People contribute because they care. But not every feature belongs in the main branch,” he said.

Papermark encourages small, meaningful pull requests and community-driven feedback, ensuring that the platform evolves rapidly without becoming bloated.

AI Meets Open Source

Marc believes we’re entering a new era where AI and open source are deeply intertwined.

He envisions a world where developers — and even non-developers — can describe features in natural language, and AI agents generate the code for them. Tools like Cursor, Windsurf, and Lovable are early steps in that direction, blurring the line between building and prompting.

“Imagine telling Papermark what feature you want, and AI builds it for you. That’s where we’re headed — personalized, one-of-one software.”

At Papermark, Marc’s already exploring ways to integrate AI review agents that help maintain code quality and filter out low-value pull requests — a glimpse of what open source collaboration could look like in the next decade.

Security, Privacy, and the Limits of “Control”

When it comes to document security, Marc is pragmatic. While Papermark can prevent downloads and track who views a file, true security often comes down to human behavior.

“You can always take a screenshot or a photo,” he said. “The goal isn’t to make data impossible to copy — it’s to make it auditable and transparent.”

In mergers and acquisitions, for example, Papermark’s audit logs help companies prove who accessed what and when — a key compliance requirement that traditional PDF sharing can’t provide.

The Future of Open Source and Startups

Looking ahead, Marc sees open source dominating more of the software stack, even at the application layer where proprietary tools once ruled.

He predicts that AI-generated code will make open source more prevalent — but less visible — as software creation moves from code editors to conversational interfaces.

For startups, the shift is clear: barriers to entry are falling, and founder-market fit is becoming the ultimate differentiator.

“You can build anything now,” Marc said. “So the question isn’t can you build it, but do you understand the problem deeply enough to solve it well?”

Final Reflections

Marc Seitz’s story is a testament to the hacker spirit — start small, move fast, stay open. From physics labs to hackathons to open-source infrastructure, his journey reflects a new kind of founder ethos: transparent, community-driven, and unafraid to challenge incumbents.

Whether you’re a developer, founder, or investor, Papermark’s rise is a reminder that the future of software isn’t just about speed — it’s about openness, collaboration, and trust.👂🎧 Watch, listen, and follow on your favorite platform: https://tr.ee/S2ayrbx_fL

🙏 Join the conversation on your favorite social network: https://linktr.ee/theignitepodcastChapters:00:01 Introduction and Guest Overview

00:28 From Physics to Software

01:41 Discovering the Physics-to-Software Path

03:06 The Appeal of Instant Feedback in Coding

04:36 Founding HackerBay

05:15 The Rise of Dropout Culture in Startups

06:14 Lessons from Early Experiments

07:25 The Hackathon Mentality

10:30 The Aha Moment for Papermark

11:39 Building an Open-Source Data Room

13:53 Why Founders Embrace Open Source

14:49 Open Source vs Proprietary Software

15:26 Selling to Enterprises and Data Sovereignty

17:14 Transparency and Trust Through Open Source

19:04 Who Uses Papermark

20:59 Licensing Models and AGPL Explained

22:27 Enforcing Open-Source Licenses

23:33 Legal and Ethical Issues in Open Source

24:50 Enterprise Adoption and Pricing

25:31 Papermark’s Growth and Free Tier

28:15 Competing with Incumbents

29:22 Community Contributions and AI Integration

30:45 AI and the Future of Open Source Collaboration

33:43 Control vs Convenience in Software

36:13 Surprising Community Pull Requests

38:22 Managing Product Bloat and Feature Creep

40:32 The Role of Maintainers and Contributors

42:04 Leveraging Community and Capital Efficiency

43:55 Building Publicly and Growing a Developer Community

46:01 AI, RAG, and Secure Document Search

47:15 Is Data Ever Truly Secure?

48:32 Transparency and Audit Logs in M&A

50:31 Evolution of Data Rooms and Compliance

51:02 Adding e-Signatures and Future Roadmap

51:49 The Future of Open Source Software

Transcript

Brian Bell (00:01:17): Hey, everyone. Welcome back to the Ignite podcast. Today, we’re thrilled to have Mark Seitz on the mic. He’s the founder of PaperMark, an open source alternative to DocSend that’s helping startups share documents more securely and affordably. Before that, Mark co-founded HackerBay, helped launch Intel Ignite in Europe and has been deeply involved in supporting founders through venture and open-source communities. Thanks for coming on.

Marc Sietz (00:01:37): Thanks so much, Brian. Thanks for having me.

Brian Bell (00:01:39): Yeah. So what’s your origin story?

Marc Sietz (00:01:41): Well, it’s pretty typical, I guess, went the traditional route through university. I actually didn’t do anything related with computer science and kind of got into that a little bit later. But primarily, I think what really got