Full Stack Engineer (f/m/d)

Clariness is looking for a Full Stack Engineer (f/md/) based in Berlin or Hamburg.
- Full-time; unlimited -

About the role:

As a Full Stack Engineer, you will help build and enhance Clariness' digital platform supporting clinical trial recruitment and patient engagement. Working as part of a cross-functional product team, you will develop new features, improve application performance, and contribute to creating scalable, high-quality software that delivers value to our users. This role is ideal for someone who enjoys solving technical challenges, collaborating with multidisciplinary teams, and continuously improving both products and engineering practices.

As a Full Stack Engineer, you would be responsible for:

• Designing, developing, and maintaining new features for our Next.js-based clinical trial platform.
• Taking full ownership of your code, features, and overall product quality.
• Optimizing application performance across APIs, databases, frontend rendering, and accessibility.
• Writing clean, maintainable, and well-tested code (unit, integration, and end-to-end).
• Collaborating closely with engineers, designers, and product managers in an agile environment.
• Participating in code reviews, technical discussions, and initiatives to reduce technical debt.
• Contributing to scalable engineering practices and the continuous improvement of our applications.

We would like you to have: 

• 2+ years of professional experience in JavaScript development, ideally with TypeScript.
• Experience with modern frontend frameworks such as Next.js, React, Angular, Vue, or Svelte. 
• Experience building backend applications using technologies such as Node.js, Express, NestJS, or Next.js.
• Solid understanding of relational databases such as PostgreSQL or MySQL; experience with NoSQL databases is a plus.
• Experience with unit and integration testing (Jest, Karma, or similar) is a plus.
• Familiarity with containerized environments (Docker, Kubernetes) is a plus.
• Knowledge of CI/CD pipelines and build tools (GitLab CI, GitHub Actions, Jenkins) is a plus.
• Degree in Computer Science, Software Engineering, or a related field, or equivalent practical experience. Next.js or AWS certifications are a bonus.
• Fluency in English.
• Strong problem-solving, communication, and collaboration skills.
• Proactive, quality-focused mindset with a passion for continuous learning and improvement.

You may ask now, why should I work for you? Let us give you a few reasons – and you'll learn more during the process.

• A varied and exciting job with a lot of personal responsibility in an international company, where you can develop and expand your skills.
• Professional and personal development opportunities - incl. personal development budget.
• Flexible working hours and mobile working.
• Regular team events and open feedback culture.
• A versatile field of activity and challenging projects.
• A supportive and open company culture, providing the opportunity to collaborate with a diverse and professional team.
• Impact healthcare by accelerating medical innovation through improved access to clinical trials, potentially bringing needed treatments to patients faster.

How to apply & what to expect: 

• Apply via link (CV only; no cover letter required).
• Introductory call (30 min) → Technical interview →  Take Home Test → Demo Day → Decision.
• We aim to move promptly and keep you updated at every step. 

At Clariness, we are proud to be an equal opportunity employer. We celebrate diversity and are committed to creating an inclusive environment for all employees, regardless of race, religion, gender, sexual orientation, national origin, disability or age.

For more information, feel free to reach out to

Have we sparked your interest?

Would you like to become part of our dynamic, curious, and international culture with plenty of room for your ideas and creativity in an inspiring atmosphere? If so, we look forward to receiving your application with details of your desired salary and possible starting date, preferably via our application portal.

Clariness GmbH will treat the above information strictly confidential and will especially observe the applicable provisions of the applicable data protection laws. Further information about the use of the applicant data, you will find in the data protection declaration online at 

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