Senior Software Engineer - FullStack (d/f/m)

Voyfai

JOIN VOYFAI, A FAST-GROWING SERIES A STARTUP SHAPING THE FUTURE OF LOGISTICS AND TECHNOLOGY ACROSS EUROPE. Headquartered in Berlin, we operate at the center of a broader group of companies active across several European markets. This is a unique opportunity to take ownership from day one, drive meaningful impact and grow within a dynamic, fast-paced environment. Whether you're shaping processes, building strategies or leading initiatives, your contributions will directly influence the success of Voyfai and the companies we support. If you're passionate about building from scratch and excited to be part of a company on the rise, we'd love to hear from you. YOUR ROLE We are seeking an experienced Senior Software Engineer (m/f/d) to play a key role in building the core infrastructure of our logistics platform. In this role, you will work closely with AI engineers and product stakeholders to define system architecture, integrate with transport management systems, and develop customer-facing features powered by large language models. Your work will be critical in shaping our engineering practices and establishing a scalable foundation for future product development over the next 12 months. KEY RESPONSIBILITIES: * Design and develop scalable software solutions with a strong focus on system architecture and clean code * Build and optimize integrations with transport management systems and third-party logistics platforms * Collaborate with AI engineers to deliver customer-facing features powered by large language models * Improve system reliability, maintainability and scalability by addressing technical debt and evolving the tech stack * Work with PostgreSQL to ensure data consistency, integrity and performance * Leverage cloud platforms such as AWS or GCP to support infrastructure and deployment * Contribute to DevOps and CI/CD practices to improve release speed and operational stability * Occasionally support customers directly, helping translate their needs into product and engineering solutions WHAT YOU BRING: * 5+ years of professional software engineering experience, with strong backend architecture skills and comfort across the full stack * Solid command of JavaScript or TypeScript across both backend and frontend contexts * Experience with SQL databases, preferably PostgreSQL * Hands-on experience deploying and operating applications on cloud platforms like AWS or GCP * Familiarity with DevOps, CI/CD pipelines and modern software development practices * Clear communication skills and the ability to collaborate effectively with technical and non-technical stakeholders * A proactive, ownership-driven mindset suited for fast-paced startup environments WHAT WE OFFER * Competitive salary and equity options * A dynamic, fast-paced work environment with a mission-driven team * Flexible working arrangements (Hybrid) * 30 days of PTO * Regular team events and offsites * Monthly mobility budget via Navit

Doctolib

What we do Join a team of passionate and hardworking entrepreneurs to transform healthcare! Working in the tech team at Doctolib involves building innovative products and features to improve the daily lives of care teams and patients. We work in feature teams in an agile environment, while collaborating with product, design, and business teams.   What you'll do We are looking for a Senior Software Engineer FullStack to join the FIRE (FHIR & Interoperability Requirements EHR) team in the Clinical domain. As a Senior Software Engineer, your mission will be to ensure that Doctolib DE is well connected to the German digital health ecosystem and compliant with FHIR standards. You will be responsible for the interoperability of the German EHR (Electronic Health Record): connection to the Telematik-Infrastruktur (TI), electronic prescriptions (eRezept), qualified electronic signature (QES), connected medical devices (GDT), and integration of laboratory results.   Your responsibilities include but are not limited to: * Build and maintain the integration with German governmental health services, ensuring other Doctolib teams can seamlessly interact with the German health system through your platform * Drive the integration of the national EHR (Electronic Health Record) into Doctolib, with a multi-country rollout approach, navigating each country's standards and technical constraints * Design, ship, and operate production-grade fullstack solutions that connect the Doctolib platform to complex healthcare infrastructure * Partner with other engineering teams to shape the architecture of Doctolib's interoperability platform * Ensure privacy, security, and compliance by design in one of healthcare's most regulated technical environments * Own performance, observability, and reliability: monitoring dashboards, SLO/SLI, and system health * Contribute to cross-functional initiatives that shape Doctolib's future interoperability strategy across Europe   About our tech environment * Our solutions are built on a single, fully cloud-native platform that supports web and mobile app interfaces, multiple languages, and is adapted to country and healthcare specialty requirements. * The FIRE team works on a FullStack scope: React / TypeScript on the frontend and Kotlin on the backend. * Our broader stack is composed of Rails, TypeScript, Java, Python, Kotlin, Swift, and React Native. * We leverage AI ethically across our products to empower patients and health professionals. Discover our AI vision here!   Who you are Are you convinced that you have exactly what it takes for the position? Then we encourage you to apply. Even if you don't meet every requirement, you might be exactly the right future Doctoliber for this or other positions! Before you read on, if you don't have the exact profile described below, but you feel this job description matches your skill set, we still encourage you to apply. * You have 6+ years of experience as a software engineer, with strong fullstack expertise, particularly in Kotlin and React/TypeScript * You have a track record of building robust, end-to-end solutions that balance technical excellence with intuitive user experiences * You are able to design systems (system design) and make sound architectural decisions in complex environments * You understand and promote best practices related to the software development life cycle: automated testing, CI/CD, and DevOps practices (you build it, you run it) * You are curious, autonomous, and have a taste for exploring new systems : you are comfortable solving problems without complete documentation * You are at ease in complex technical environments with many external dependencies and evolving standards * You are eager to share your knowledge and help the team grow through pair programming and mentoring * You are comfortable speaking and writing in English in your day-to-day with the team, German is a plus Now, it would be fantastic if you: * Have experience with healthcare interoperability standards, particularly FHIR, HL7, or similar * Have experience integrating with governmental or regulated health systems (e.g. Telematik-Infrastruktur, eRezept, GDT) * Are familiar with the German digital health ecosystem   What we offer * A Deutschlandticket (Germany-wide public transport pass) fully paid for by Doctolib * 28 vacation days + 1 additional day for each full calendar year of employment (up to a maximum of 30 days) * Work from abroad for up to 10 days per year thanks to our flexibility days policy * Company health insurance with great supplementary benefits through our partner Allianz * Company pension scheme (bAV) through Allianz with an employer subsidy of 40% (15% within the probationary period) * Enrollment in Doctolib's long-term employee value sharing plan called DoctoGrowth * The Doctolib Parent Care program, which includes one month additional parental leave and much more * Free mental health and coaching services through our partner Moka.care * Subsidized sports membership through our partner Urban Sports Club * A flexible workplace policy offering both hybrid and office-based mode * Alongside healthy snacks and our regular breakfast buffet, we provide a subsidized meal benefit * For caregivers and workers with disabilities, a package including an adaptation of the remote policy, extra days off for medical reasons, and psychological support   The interview process * Recruiter Interview * Feature Building Interview * System Design Interview * Behavioral Interview * Reference check * Offer! Job details * Full-time * Location: Berlin * Working mode: Hybrid * Start date: as soon as possible If you would like to find out more about tech life at Doctolib, feel free to read our latest Medium blog articles! At Doctolib, we are committed to improving access to healthcare for everyone. This translates into our recruitment process. We evaluate candidates based solely on qualifications and motivation, without any form of discrimination. The more diverse ideas are heard, the more our product will truly improve healthcare for all. You are welcome to apply to Doctolib, regardless of your gender, religion, age, sexual orientation, ethnicity, disability. To ensure equal opportunities, we invite you to exclude personal information (e.g. pictures, age) from your applications. If you require any accommodation, please let us know for support during the hiring process.  Join us in building the healthcare we all dream of! All information provided is processed by Doctolib for application management. For data processing details, click here. Please contact hr.dataprivacy(at)doctolib.com for inquiries or to exercise your rights.

Taxfix

OUR STORY: Every year millions of people are either filing their taxes in fear or giving up on their tax refund altogether. We're working on fixing that. Our intuitive app enables anyone, regardless of education or background, to file their taxes with newfound confidence. Spread across Germany, Spain and the UK, the team at Taxfix Group with its brands Taxfix and Steuerbot, is a compassionate group of solution-finders. We speak our minds openly, and with over 400 professionals, including tax experts, developers, and IT security experts, we're rich in ideas and voices. The group has facilitated more than 3.5 billion euros in tax refunds for its customers since its founding in 2016. YOUR CHALLENGE As a (Senior) Software Engineer on the TaxCore team, you'll be part of a shared engineering team that serves both Taxfix and Steuerbot - one team, two brands, multiple products. Based in Berlin or Stuttgart with a flexible hybrid setup, you’ll build and evolve the core shared services that power core experiences across both brands. In close collaboration with other teams, you'll design scalable backend systems and help shape technical direction as part of a small, high-ownership team that moves fast without cutting corners. This is a role for someone who loves building things that matter - and who takes genuine pride in the craft of doing it well. YOUR RESPONSIBILITIES * Build, maintain, and continuously improve core shared services and internal tools that power stable, intuitive user experiences for both Taxfix and Steuerbot. * Design and implement scalable, reliable backend systems and architecture that enable core functionality across Taxfix and Steuerbot. * Collaborate across teams to design, ship new features and share capabilities, working pragmatically beyond the boundaries of your immediate team. * Contribute to shaping the long-term technical direction of core backend services, bringing both depth of expertise and a pragmatic, outcome-focused mindset. * Contribute across the team’s stack, including occasional frontend work on internal tooling. * Take ownership, remove blockers, and help the team stay focused on what matters most. YOUR PROFILE * You bring strong backend engineering experience and a proven track record of building and evolving complex, scalable systems in production environments. * You are highly proficient in at least one modern programming language, and experience with Go is strongly preferred. * You have solid experience with modern software architecture concepts, including API design, databases, and cloud-based systems - and hands-on experience integrating a diverse range of third-party and internal APIs. * You are comfortable with containerization and DevOps concepts, with practical experience using tools like Kubernetes. * You care deeply about code quality - writing performant, maintainable, and elegant code is something you take genuine pride in, and you have a natural affinity for the full stack of what it takes to ship great software. * You are familiar with AI-assisted development tools like Claude Code, and understand how to use them thoughtfully to support better, faster engineering. * You’re a pragmatic, hands-on builder: someone who cuts through complexity and enjoys turning ideas into well-crafted solutions. * You’re collaborative, direct, and outcome-oriented, and thrive in cross-functional environments where people work closely together to solve problems. * German language skills are a plus, as this team works closely with Germany-specific tax logic. WHY TAXFIX?  * A chance to do meaningful, people-centric work with an international team of passionate professionals. * Holistic well-being with free mental health coaching sessions and yoga. * A monthly allowance to spend on an extensive range of services that you can use and roll over as flexibly as you like. * Employee stock options for all employees—because everyone deserves to benefit from the success they help to create. * 30 annual vacation days and flexible working hours. * A generous learning budget to support your personal and professional development and guidance from our internal L&D experts. * Work from abroad for up to six weeks every year. Just align with your team, and then enjoy your trip. * Plenty of opportunities to socialise as a team. In addition to internal meetups, our international team hosts regular get-togethers—virtually and in person when possible. * Free tax declaration filing, of course, through the Taxfix app—and internal support for all personal tax-related questions. * Have a four-legged friend in your life? We’re happy to have dogs join us in the office. Excited? So are we. Learn more about Team Taxfix on our blog and get a glimpse of our culture.   At Taxfix, we believe that incredible things happen when you have a wealth of perspectives and experiences. We're proudly committed to equal employment and development opportunities no matter your gender, race, religion, age, sexual orientation, colour, disability, or place of origin. To help mitigate any potential unconscious biases, we ask that you refrain from including your picture, age, or marital status on your CV. Let your experiences speak for themselves. Not sure if you meet all the requirements for this role? Please apply anyway. You might bring something special to the team that we hadn't considered previously.