Senior Software Engineer | API

DeepL DeepL is a global AI product and research company focused on building secure, intelligent solutions to complex business problems. Over 200,000 business customers and millions of individuals across 228 global markets today trust DeepL's Language AI platform for human-like translation, improved writing and real-time voice translation. Founded in 2017 by CEO Jaroslaw "Jarek" Kutylowski, DeepL now has around 1,000 passionate employees and is supported by world-renowned investors including Benchmark, IVP, and Index Ventures. Our goal is to become the global leader in trusted, intelligent AI technology, building products that drive better communication, foster connections, and create a meaningful impact. To achieve this, we need talented people like you to join our journey. If you're ready to shape the future of AI and grow your career in a fast-moving, purpose-driven environment, DeepL is your next destination. What Sets Us Apart What sets us apart is our blend of cutting-edge AI technology, meaningful work, and a culture where people truly thrive. We're a team of innovators, researchers, and creators driven by a shared purpose to unlock human potential by making work simpler, smarter, and more connected. When we share what it's like to work at DeepL, the reactions are overwhelmingly positive. This might be because of our technology that helps millions of people and businesses communicate and work better every day, or because of the trust, curiosity, and care that shape our culture. What we know for sure is this: being part of DeepL means joining a team dedicated to innovation, growth, and well-being. Meet The Team Behind This Journey DeepL is not just a translation tool; we are building the Operating System for Global Communication. We are the rare AI company that builds the entire stack in-house: from training next-gen LLMs on our own NVIDIA DGX SuperPODs to delivering real-time Language AI to over 300 million users and 200,000+ businesses globally. You will join the API Core team. For us, the API is the product. We are the bridge connecting DeepL's bleeding-edge AI capabilities to developers worldwide. We focus on Developer Experience (DevEx), API platform infrastructure, and enabling our internal product teams to launch world-class APIs quickly and independently. We are shifting gears from "Software-First" to "Product-First." We don't hire engineers to simply maintain legacy endpoints or close Jira tickets. We hire Missionaries—builders who obsess over the Why before the How. You will balance strategic platform architecture with tactical feature delivery, working across the stack to create delightful, frictionless experiences for both external developers and internal engineering teams. Your Responsibilities Drive "DevEx Delight": You will own and transform the experience of developers using DeepL APIs. You will streamline the entire journey—from anonymous visitor to activated developer—by building intuitive self-service experiences, seamless onboarding flows, and advanced customization interfaces. Platform Enablement & Scale: You won't just write endpoints; you will build the ecosystem. You will create reusable components, comprehensive documentation, starter templates, and client libraries (SDKs) that empower customers and ISVs to build AI-enabled products rapidly. Cross-Functional Architecture: You will act as the API standard-bearer across DeepL. Partnering with Enterprise (BAT), Core Text, Voice, and Customization teams, you will drive continuous improvement and maintain the highest standards for the consistency, security, and reliability of all customer-facing APIs. Guardianship of Quality & Compliance: You will implement automated quality gates, strict contract testing, and robust monitoring infrastructure. You will prevent breaking changes and security vulnerabilities before they hit production, shaping the API design standards and operational excellence practices for our growing platform. Qualities We Look For A "Product-First" API Mindset: You treat developers as your primary users. You understand that a successful API relies on reducing cognitive load, creating clear abstractions, and providing stellar documentation, not just fast response times. Backend Mastery & Full-Stack Capability: You have deep expertise in designing scalable backend systems, RESTful APIs, and distributed architectures (using Go, Python, Java, C#, or similar). You are also comfortable crossing the stack, using modern frontend frameworks (React/TypeScript) to build developer-facing dashboards, signup flows, and configuration UIs. Extreme Ownership & Operational Excellence: You have a track record of owning services end-to-end. You don't just ship code; you own production operations, incident response, and continuous improvement. You write comprehensive tests, learn from incidents, and treat mature SLOs as a core engineering feature. AI-Native Velocity: You leverage AI-powered tools (like GitHub Copilot or Claude) to accelerate your velocity and eliminate repetitive toil. You use AI for boilerplate code, test generation, and debugging, allowing you to focus your cognitive energy on high-value architectural decisions and complex problem-solving. What We Offer Diverse and internationally distributed team: joining our team means becoming part of a large, global community with people of more than 90 nationalities. We're more than just colleagues; we're a group of professionals with a shared mission to connect diverse cultures. Our global presence is growing–we've doubled in size nearly every year, with our employees based in the UK, Germany, the Netherlands, Poland, the US, and Japan, and we continue to expand our network. Open communication, regular feedback: as a language-focused company, we value the importance of clear, honest communication. We value smooth collaboration, direct and actionable feedback, and believe that leading with empathy and growth mindset makes us better together. Hybrid work, flexible hours: we offer a hybrid work schedule, with team members coming into the office twice a week. This allows you to engage directly with your team and experience the unique energy of our workspace, while still enjoying the flexibility and comfort of working from home. With flexible working hours and trust in your productivity, we are in sync with your team's general locations and time zones to foster effective and seamless collaboration. Virtual Shares - An ownership mindset in every role. We believe everyone should share in our success, and that's why every employee receives Virtual Shares, linking your contribution directly to DeepL's growth and rewarding you with a stake in our future. Regular in-person team events: we bond over vibrant events that are as unique as our team, from local team and business unit gatherings, to new-joiner onboardings, to company-wide events that bring us all together–literally. Monthly full-day hacking sessions: every month, we have Hack Fridays, where you can spend your time diving into a project you're passionate about and get the opportunity to work with other teams–we value your initiatives, impact, and creativity. 30 days of annual leave: we value your peace of mind. With 30 days off (excluding public holidays) and access to mental health resources, we make sure you're as strong mentally as you are professionally. Competitive benefits: just as our team spans the globe, so does our benefits package. We've crafted it to reflect the diversity of our team and tailored it to align with your unique location, to ensure you feel supported every step of the way. If this role and our mission resonate with you, but you're hesitant because you don't check all the boxes, don't let that hold you back. At DeepL, it's all about the value you bring and the growth we can foster together. Go ahead, apply - let's discover your potential together. We can't wait to meet you! DeepL