Lead Software Engineer - Integrations

We're looking for a Lead Software Engineer to help shape the future of our Integrations team in Berlin - the platform that connects Nelly to the practice management systems (PMS) our customers already run, and that lets every other product team at Nelly ship reliable, automated workflows into dental practices without ever touching PMS complexity themselves.

About the team

Integrations is the connective tissue between Nelly and the outside world. Our stack spans the full spectrum of how a practice can be reached - from talking directly to on-premise systems and their databases, through modern API integrations, up to cloud infrastructure, and increasingly AI-powered capabilities that make integrations smarter and more resilient.

That means supporting legacy industry protocols, integrating directly at the database level, and, when there's truly no other way in, driving a PMS's UI the way a human would - all wrapped behind a resilient, observable transaction engine that other product teams (Billing Agent, AI Scribe, Treatment Plan Agent, and more) build on top of without thinking about PMS quirks at all.

It's some of the most technically interesting, and most business-critical engineering at Nelly: every transaction that lands (or doesn't) in a practice's system has a direct line to revenue, and our reliability numbers are watched company-wide. We're a small, senior team that owns this end-to-end, from the client software running on a practice's own server to the architecture decisions that shape how the rest of engineering builds on top of us.

About Nelly

We are building the AI-Driven Financial Operating System for European healthcare, solving the biggest challenges for patients and practices. We create what no bank or software platform can handle. Our all-in-one platform transforms chaotic administrative processes into intelligent, automated workflows, from patient care to billing to next-generation payments. Because we truly believe: healthcare should be less about paperwork and more about people.

Why? Because Europe is facing a massive shortage of medical professionals. And if we don't rethink the way practices work, the system won't be able to keep up. With our Series B funding of over €50 million from world-class investors, we are turning our vision into reality.

What sets us apart: We work with the best team, which is why we give everything together every day. We believe in Talent Density, because exceptional people make everyone around them better. At Nelly, we move fast and expect everyone to keep up. Stagnation isn’t an option, which is why we invest heavily in growth. AI is an essential part of how we work at Nelly. We expect you to use it every day and give you everything you need to do so. You get trust and ownership and we expect you to speak up, even when it's uncomfortable.

Joining us, you will:

• Be the technical authority the team turns to on the hardest calls - the person other teams seek out for input, not just within Integrations
• Own and evolve the architecture of the Integrations platform - from the on-practice client through the transaction engine - and set the technical direction other engineers build on.
• Build connections between practice management systems and Nelly's backend, working hands-on with modern technologies. We host everything on AWS and manage our infrastructure as code
• Take ideas from concept to production fast, with your work reaching customers within your first few days
• Help define our mid- to long-term technical strategy - the roadmap, patterns and investments that let Integrations keep enabling the product vision as the team and company scale.
• Raise the bar on engineering practices across the team, including how we use AI tooling to make engineering faster and better - you don't just use new tools, you help the team adopt them.
• Explore and ship AI-powered capabilities inside the integration platform itself - not just using AI as an engineering tool, but building it into the product (smarter matching, anomaly detection, automated triage, and more).
• Work closely with other engineering teams and with non-technical, non-product stakeholders - inside and outside the domain (Product, Commercial, Support, Legal, external PMS/partner contacts) - translating technical trade-offs into terms that land on both sides.
• Mentor and coach engineers on the team, and act as a technical thought partner across teams

What you'll bring:

• At least 7 years as a software engineer, with a track record of technical leadership - owning architecture decisions, mentoring others, and driving initiatives across teams
• Strong computer science fundamentals and systems-level thinking
• Proficiency in data and API modelling
• Knowledge of software engineering best practices for the full development life cycle.
• Strong communicator and team player - equally comfortable working with engineers on other teams and with non-engineering stakeholders
• Willingness to pick up new languages and technologies fast - you don't need to already know our stack, but you're confident you can learn it quickly
• Experience using - and introducing - AI tools to make yourself and your team more effective, not just as a user but as someone who champions adoption
• Experience working in a highly cross-functional, multi-stakeholder environment, like Integrations, where you're coordinating across many internal teams and external parties

Nice to have:

• Comfortable working across the full stack - from device- and database-level integration, through APIs, up to cloud infrastructure
• Experience with AWS, security best practices and Windows Native APIs
• Experience deploying and supporting software across many different customer environments and setups (e.g. on-premise installs, varied client infrastructure)
• Proficiency in English; German is a strong plus

What we offer:

• The people you get to work with. You will work alongside the brightest minds we could find, on hard problems, as a team. We take on challenges together and we never forget to have fun doing it.
• Room to grow faster than almost anywhere else. New challenges, more scope, real ownership from day one. We trust you to own it and to speak up when something is wrong. Just do not expect to stand still.
• A yearly learning and development budget, plus the coaching, feedback and internal knowledge that actually move you forward. Real investment in your learning.
• A front row seat while we build something big. We are building the financial operating system for European healthcare, with AI woven into how we build, sell and support. Real scope, real impact.
• Deutschlandticket or Swapfiets membership.
• Urban Sports Club membership.
• Flexible working hours and a hybrid setup and up to 4 weeks of workation.
• A dog friendly office.

We welcome applications from people of all genders and backgrounds, regardless of origin or age. If you're convinced you're the right fit for this role - even if your CV doesn't match the requirements 100% - tell us why.