Senior Software Engineer | API

MEET 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. Discover more about life at DeepL onLinkedIn https://www.linkedin.com/company/deepl/,Instagram https://www.instagram.com/deepl_official/, and our Blog https://www.deepl.com/en/blog. 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 100 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 preven