Senior Fullstack Engineer

The Opportunity

We are looking for a great colleague to join our EY Tech People team as a Senior Fullstack Engineer, where you will play a pivotal role in building innovative tax automation tools and AI-integrated platforms across several business-critical products. Our mission is to enhance efficiency, quality, and satisfaction in tax and compliance workflows, serving thousands of clients with accurate and compliant tax filings. As part of a dynamic organization operating across the Nordics (DK, FI, SE, NO), you will collaborate with a talented group of engineers, designers, researchers and product managers in a flat, informal structure. While experience in tax law is beneficial, a passion for technology and collaboration is what we truly value.

Your Key Responsibilities

• Building end-to-end tax automation features from React frontends to Node.js backends 

• Developing AI-integrated platforms with seamless user experiences and robust data processing 

• Close collaboration with designers, product managers, and fellow developers as well as sparring with users and researchers to understand tax workflows in detail 

• Contributing to internal tooling and developer experience, including AI-assisted development workflows, MCP server implementations, and prompt libraries 

• Working across a range of products and problem spaces in the fullstack domain 

Skills and Attributes for Success

To thrive in this role, you possess a strong foundation in both frontend and backend technologies. To qualify for the role, you should have: 

Frontend Expertise (Required): 

• React/TypeScript: Extensive experience with modern hooks, state management, and performance optimization 

• Modern Tooling: Experience with build tools (Vite/webpack), testing frameworks (Cypress/Playwright), and Kubernetes deployments 

• Complex UI Development: Building multi-step workflows, sophisticated form validation, and responsive interfaces 

Backend Proficiency (Required): 

• Node.js: Extensive experience with Express, async programming, and RESTful API development 

• MongoDB: Strong experience with document design, aggregation pipelines, and performance optimization 

• Python Integration: Experience with FastAPI, report generation, and GenAI pipeline integration 

• System Integration: Third-party API integration, microservices patterns, and MCP implementations 

What We Look For

We are seeking a detail-oriented Fullstack Engineer with the ability to communicate technical concepts clearly with both technical and non-technical stakeholders. We imagine you as someone quick to solve complex problems and with the ability to question technical approaches and challenge architectural decisions. You are also eager to learn about advancements in fullstack technologies and tax domain complexities. A practical engineering mindset focused on delivering impactful solutions will help you succeed in this role. Furthermore, our new colleague is someone who embodies more than just technical expertise. We are looking for a supportive team member, ready to share knowledge and help others grow. You are based in either Copenhagen, Helsinki or Stockholm.

What We Offer 

• A tech product team: EY’s Tech People organization as a unit operates mostly product- and user-driven, even though we are situated within a large consultancy organization 

• Direct access to users: Your fullstack solutions will directly impact tax professionals who are quite literally right next to you, providing immediate feedback on both UX and system performance 

• Full-stack ownership: Take features from concept to deployment with complete technical ownership 

• Technology growth: Work with other great Engineers on React patterns, Node.js performance optimization, and AI integration challenges among other things. 

• Good food and good times: We take good care of the people who dedicate their working hours to our cause 

• Diverse and inclusive culture: You'll be embraced for who you are and empowered to use your voice to help others find theirs 

Please apply with your CV and Cover Letter no later than March 22nd, 2026. We review applications on an ongoing basis so please apply right away. For questions regarding the role, do not hesitate to contact brian.groth@dk.ey.com  If questions regarding the recruitment process, please contact maria.thuy.truong@ey.com. We look forward to your application!