The enterprise software development landscape faces a mounting crisis: massive codebases trapped in technical debt, security vulnerabilities spreading across thousands of repositories, and development teams drowning in manual refactoring work. For Jonathan Schneider, CEO and Co-Founder of Moderne, this challenge isn’t theoretical—it’s a problem he’s been solving for over a decade, starting with his days at Netflix.

In a recent interview on TFiR, Schneider revealed how Moderne has evolved from addressing internal Netflix pain points to revolutionizing enterprise code modernization through their OpenRewrite open source project and commercial platform. The company’s mission remains focused on “large scale source code refactoring” including application modernization, vendor lock-in escape routes, and security vulnerability repair across multiple repositories.

How a Painful Netflix Migration Inspired OpenRewrite: The Open Source Engine Powering Moderne

Schneider, who previously worked at Netflix and Pivotal, conceived the idea of automated refactoring after witnessing firsthand the sheer waste of time and talent in large-scale code migrations. At Netflix, replacing a legacy logging library across millions of references revealed a pain point shared by many enterprises: the need to automate mundane but necessary code transformation tasks.

That spark led to the creation of OpenRewrite, the open source project at the core of Moderne’s platform. While OpenRewrite handles day-one developer problems one repo at a time, Moderne takes it several steps further—enabling organizations to refactor thousands of repositories using its proprietary lossless semantic tree (LST) technology. This makes it computationally feasible to execute recipes across massive codebases without compromising performance or accuracy.

Balancing Open Source and IP: The Shift to Source-Available Licensing

Schneider emphasized the value of keeping the core refactoring engine open source but highlighted the need for differentiated licensing models. “I’m deeply pro–open source. The core refactoring engine remains Apache-licensed. But AI tools can now run open source tools without attribution, as we saw with Amazon Q Code Transformation. So, source-available licensing helps us protect our work while fostering partnerships instead of competition,” Schneider noted. This growing trend—where AI-powered tools obscure the underlying OSS that powers them—has prompted Moderne to adopt source-available licenses to safeguard its innovation.

Unlike IDE-focused AI code agents that help developers write new code, Moderne complements these tools by working with everything else—the massive amount of existing code not actively open in an IDE. Through its serialized LSTs, Moderne enables AI and recipe-based transformations to be applied across an entire business unit, enabling impactful changes like Java migrations, security fixes, or cloud vendor transitions.

Driving Real-World Impact: Lessons from Code Remix Summit

And the results are real. At their recent Code Remix Summit, Moderne facilitated hands-on modernizations with attendees across multiple tracks—including developers, leaders, and a unique “Hack Track.” The goal? To do real work, not just talk.

Schneider also shared how Moderne integrates closely with enterprise clients—often embedding consultants or technical account managers into their teams to co-develop custom transformation recipes. This blend of out-of-the-box and tailored support creates immediate and measurable business value.

Competing with Manual Labor, Not Other Tools

Ultimately, Schneider sees the competition not as other tools, but manual labor itself. By lowering the cost and time of modernization, Moderne opens the door to transforming stacks that previously were too expensive or complex to touch.

For enterprises looking to modernize at scale—whether for performance, compliance, or innovation—Moderne offers not just a tool, but a transformation in approach.

Edited Transcript

Swapnil Bhartiya (Host): Today, we are diving into the world of automated code modernization with Jonathan Schneider, CEO and Co-Founder of Moderne. Jonathan leads Moderne, a company tackling one of the biggest challenges facing enterprise development teams today: modernizing massive codebases at scale.

Through their open source Rewrite project and the commercial Moderne platform, they’re helping organizations transform legacy code in minutes, not months—a critical capability as companies race to keep pace with evolving technologies and security requirements.

In this conversation, we’ll explore how Jonathan’s team built OpenRewrite as an open source foundation, how Moderne differentiates itself in the crowded developer tools market, and how their AI-powered code agent fits into the future of software development. We’ll also discuss their recent Code Remix Summit and how enterprises are measuring real value from automated code modernization.

Jonathan, it’s great to have you back on the show.

Jonathan Schneider (Guest): It’s great to be back, Swapnil. My pleasure.

Host: It’s been a while—last time we spoke was four years ago. Just to reintroduce Moderne to our audience, can you tell us about the company, the problem you’re solving, and how things have evolved over the past few years?

Guest: Moderne is all about large-scale source code refactoring—application modernization, escaping vendor lock-in, migrating from one vendor to another, and repairing security vulnerabilities. Basically, anything that needs to change across many repositories.

Host: How has the market evolved in the last four years? Has your mission changed?

Guest: The mission has remained consistent. I started this journey over a decade ago at Netflix, creating OpenRewrite to address refactoring challenges. Later, at Pivotal on the Spring team, I saw how acute this pain point was for large enterprises. When we launched Moderne in 2020, people doubted that large-scale code refactoring was even feasible. AI has now lifted that veil of disbelief and opened the door for this solution space.

Host: What was your initial goal with OpenRewrite?

Guest: It started with trying to remove an old logging library at Netflix—something no one wanted to do manually. We were seeking automation. That grew into larger goals like Java 8 to 17 migrations, switching IAM providers, or database transitions. Enterprises were even building internal software factories just to do this repetitive work, which has become economically unsustainable.

Host: Open source can handle day-one challenges, but day-two needs commercial support. How do OpenRewrite and Moderne relate?

Guest: The difference is scale. OpenRewrite runs recipes one repository at a time, and the runtime is tied to compile time. At enterprise scale—say, 200,000 repos—that’s inefficient. Moderne pre-serializes the data (what we call a lossless semantic tree), making recipes run at scale efficiently. We also offer a mix of open, source-available, and proprietary recipes for key use cases.

Host: What’s your approach to open source licensing?

Guest: I’m deeply pro–open source. The core refactoring engine remains Apache-licensed. But AI tools can now run open source tools without attribution, as we saw with Amazon Q Code Transformer. So, source-available licensing helps us protect our work while fostering partnerships instead of competition.

Host: How does AI factor into this?

Guest: AI code tools rely on IDE-level context—abstract syntax trees and type-attributed representations. Moderne builds on that by serializing this context (the LST) across all repos in an org, not just what’s open in an IDE. This enables large-scale changes with the same contextual awareness AI tools use for small files.

Host: Would you say Moderne complements AI-powered code agents?

Guest: Yes—completely. Code agents help you write new code in your IDE. Moderne operates on code you don’t have open. The opportunity to modernize at scale has been ignored because most AI work has focused on writing, not maintaining, code.

Host: How do you engage with enterprises? Is it turnkey or collaborative?

Guest: It’s a mix. Some customers use our recipes out of the box. But for larger clients, we embed technical account managers who build custom recipes and work directly with teams. The combination of out-of-the-box and tailored recipes delivers maximum impact.

Host: Who do you consider your competitors?

Guest: Manual labor. Traditionally, this work was done manually or through systems integrators. But we’re not replacing them—we’re making it cheaper and more scalable. There’s more modernization work out there than people do it, so lowering cost just unlocks more progress.

Host: What about security? How do you avoid introducing new bugs?

Guest: Great question. As Linus once said, bugs are inevitable. Recipes are programs, and programs can have bugs. But since recipes apply across orgs, once a bug is fixed, the fix propagates. We deploy new recipes to small teams first, then expand as confidence grows. That’s our QA and rollout model.

Host: Tell us about the recent Code Remix Summit.

Guest: It was our first year—150 attendees in Miami. We had three tracks: developer, leadership, and a hack track. The hack track was hands-on: attendees came prepared, worked with experts, and executed real-world modernizations. We’re doubling it next year and will continue building a strong technical community around this space.

Host: Thank you, Jonathan, for your time and for explaining how Moderne is making a huge difference in modernizing legacy and even modern codebases. Let’s not wait another four years before the next chat!

Guest: Thank you, Swapnil. Always a pleasure.