Senior Software Engineer | Full-Stack

Company Overview

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 trust DeepL's Language AI platform for human‑like translation, improved writing and real‑time voice translation. Building on a history of innovation, quality and security, DeepL continues to expand beyond the field of Language, including DeepL Agent – an autonomous AI assistant designed to transform the way businesses and knowledge workers get work done. Founded in 2017 by CEO Jarek Kutylowski, DeepL now has over 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. We are a team of innovators, researchers, and creators driven by a shared purpose to unlock human potential by making work simpler, smarter and more connected. We are building the Operating System for Global Communication, and we are moving from “Software‑First” to “Product‑First.” We hire Missionaries who obsess over the Why before the How.

Role Overview

As a Senior Engineer at DeepL, you will operate with the agency of a founder. You will join a high‑performance engineering culture that values shipping speed, system reliability and direct business impact over theoretical perfection. Whether you are building our next‑gen Voice API, architecting our massive billing engine or scaling our core product platform, you will own your domain end‑to‑end.

Responsibilities

• Own the Outcome, Not Just the Code: You will move beyond “implementing specs.” You will own revenue‑critical systems from the initial problem definition through to architectural design, deployment and production reliability. You measure success by user impact, not just pull requests merged.
• Architect for Ambiguity: You will make high‑stakes technical decisions (monolith vs. microservice, consistency vs. availability) with incomplete information. You don't wait for perfect requirements; you identify risks, build prototypes and iterate based on real‑world feedback.
• Bridge the Gap: You will be bilingual in “Engineering” and “Business.” You will translate complex technical constraints (latency, eventual consistency) into business terms for Product Managers, ensuring we negotiate the right trade‑offs to ship value faster.
• Drive Technical Pragmatism: You will avoid “Resume‑Driven Development.” Whether using our core stack (C#/.NET Core, Python, Kubernetes, React) or exploring new tools, you choose the technology that solves the customer problem most effectively, ensuring long‑term maintainability over short‑term trends.

Qualities We Look For

• A “System Thinker” Mindset: You don't just know syntax; you understand failure modes, system boundaries, and how your code impacts the broader architecture at scale. You can design systems that survive 10x growth.
• High Agency & Bias for Action: You don't wait for permission. If you see a fire, you put it out. If the documentation is missing, you write it. You are comfortable unblocking yourself and the team in a fast‑paced environment.
• Product Fluency: You care deeply about the user. You ask “Why are we building this?” before writing a line of code. You have a track record of shipping features that solve real business problems.
• Polyglot & Adaptable: While experience with C#/.NET Core or React is a bonus, we value engineers who can pick up the right tool for the job. You are comfortable traversing the full stack, from the database lock to the UI state.
• 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.

Hiring Process

DeepL hires for the company, not just a specific team. We operate a Unified Engineering Pipeline. If you pass our bar, we will match you to the highest‑priority role that fits your skillset—whether that is in Core Product, Platform, Voice or Enterprise. We prioritize “Missionaries” who want to solve the biggest problems, wherever they live in the stack.

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. Our global presence is growing–we've doubled in size nearly every year, with employees based in the UK, Germany, the Netherlands, Poland, the US and Japan, and we continue to expand our network.
• Open communication, regular feedback: we value clear, honest communication. We value smooth collaboration, direct and actionable feedback, and believe that leading with empathy and a 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. 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 unique to 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: 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: we crafted the package 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.

Equal Opportunity Statement

You are welcome at DeepL for who you are – we appreciate authenticity here. Our product is for everyone, and so is our workplace. The more voices we have represented and amplified in our business, the more we all succeed, contribute and think forward. Bring us your personal experience, perspectives and background. It’s in our diversity that we will find the power to break down language barriers in the world.