Meet 5 Architects, Innovators, and Leaders Behind MongoDB’s Community

Developers, data architects, and innovators from around the world gathered in the fall of 2025 for MongoDB.local London, an educational conference with keynote speeches, technical sessions, product demos, and networking opportunities, all focused on data-driven application development. This group came together to swap stories, share lessons, and get a first look at what’s next for MongoDB—and the energy felt palpable and, frankly, contagious.

Many of our MongoDB Community Champions joined us in London. These are passionate experts who give back to the community by teaching, mentoring, and inspiring others. We asked a handful of these champions how they’re putting MongoDB to work—and what being part of this dynamic global community means to them.

Patrick Pittich-Rinnerthaler, Totally Nerdy

Based in the U.K., Patrick Pittich-Rinnerthaler is managing director of Totally Nerdy, a web consultancy he co-founded in 2019. Pittich-Rinnerthaler has 20 years of experience working in web architecture and has used MongoDB since 2011, drawn to its ease, speed, and document-oriented design. “I like that you have flexibility,” Pittich-Rinnerthaler said. “You can work in a relational way, but if you want to be fast, you can embed everything into one collection.”

As a MongoDB Champion, Pittich-Rinnerthaler channels his experience back into the community by sharing tutorials, speaking at events, and mentoring peers. “Being a champion lets me validate my knowledge and learn from others—iron sharpens iron!” he said. Whether optimizing enterprise systems or building on his own MongoDB-powered platform, tyny.dev, Pittich-Rinnerthaler is driven by a passion for smarter, faster development.

Mateus Leonardi, HeroSpark

HeroSpark, a fast-growing Brazilian SaaS company, helps creators and small businesses sell courses and manage payments. When Mateus Leonardi joined as CTO, he faced a rocky start with MongoDB. “At first I hated it,” he admitted, after struggling with a self-hosted community edition. “But the problem wasn’t MongoDB itself—it was that we were trying to run and manage it on our own. We didn’t have the expertise for that. Moving to a managed service removed that burden and let us focus on using MongoDB properly.” A 36-hour outage convinced Leonardi to migrate to MongoDB Atlas, promising stability in nine months and delivering it in three.

With MongoDB Atlas handling infrastructure, Leonardi transformed a fragile system into a scalable backbone powering half the company’s revenue. He then did the same with new products such as HeroSpark’s payment platform and AI-driven support tools.

As an enthusiastic MongoDB Champion, Mateus shares his knowledge across Brazil’s developer community, mentors his peers, and advocates for regional needs. “Before, I had a narrow vision,” he said. “Now, I can see 360 degrees.” For him, MongoDB has become both a technical partner and a platform for giving back.

Nenad Milosavljević, Flatfee

Flatfee, a US- and China-based legal tech startup, helps small and medium-sized businesses navigate cross-border legal services—from company registration to patents and compliance—without expensive law firms. Its platform is now expanding into AI-driven global compliance, using vector embeddings and image similarity searches to detect product and trademark infringements.

MongoDB Atlas sits at the core of Flatfee’s systems, powering everything from user data to complex business logic. Nenad Milosavljević, a Flatfee senior software developer, has found MongoDB’s flexibility to be transformative for his work and their business. “It maps one-to-one with the objects in my code,” he said. “I can adapt and evolve the schema without migrations. It’s very cool.” 
As a MongoDB Champion, Milosavljević shares his expertise through blogs, certification design, and running his own MongoDB user group in Serbia. “I like development, networking, and meeting other people,” he added. For Milosavljević and Flatfee, MongoDB fuels both innovation and a growing community.

Carla, financial group

Carla has spent over 15 years as a database technology expert in one of Iberia’s largest financial groups, where SQL Server and rigid relational models have long dominated the landscape. She’s now helping to power a quiet revolution. When her team ran a proof of concept with MongoDB Community Edition to track IT assets for EU DORA compliance, the results spoke for themselves: faster performance, more streamlined structures, and real-time insights that all came from a single collection.

Encouraged by that success, the bank has moved toward adopting MongoDB Enterprise Advanced, with Carla co-steering both the technical and cultural change. As a recent MongoDB Champion nominee, Carla shares that drive beyond her organization by running training sessions, writing articles, and exchanging knowledge with peers across Europe. “I’m learning so much,” she said. “Not just the technology, but from other cultures and use cases. It’s very enriching.”

Xiao Lei Dai, Zhihu

Tens of millions of people visit Zhihu every day - a high-quality Q&A community and original content platform where creators gather on the Chinese internet. Behind the scenes, Xiao Lei Dai keeps it all running. With 15 years of database experience, he leads Zhihu’s database architecture team, managing around 40 MongoDB clusters, the largest holding 250 terabytes and handling a million queries per second.

MongoDB powers Zhihu’s anti-spam and moderation systems, quietly checking every post before it goes live. “When someone asks a question, it doesn’t go live straight away,” Dai explained. “It’s reviewed against a set of rules stored in MongoDB. If it passes, everyone can see it.”

As a MongoDB Champion, Dai shares his expertise far beyond Zhihu. He organizes meetups, speaks at conferences, and unites China’s growing MongoDB community. “Being a champion helps me connect with experts around the world,” he said.