Senior Fullstack Developer

Our client is leading in secure documentation and authentication solutions, setting the benchmark for safety and trust.

As a Senior Full Stack Developer, you’ll join the core team driving product, support and customer projects, working closely with the lead developer as a trusted sparring partner.

The ideal candidate brings a holistic view of modern IT—spanning software architecture, database design, and DevOps practices—combined with the confidence to make smart, impactful decisions.

For maximum security, all infrastructure is operated entirely on-premise.

• Product Development & Customer Projects – Work within the core team to maintain and enhance products while driving client-specific implementations.
• Technical Partnering – Act as a sparring partner for the lead developer, contributing to architecture, database design, and decision-making.
• Security-Driven Development – Apply DevOps practices and holistic IT expertise in an on-premise infrastructure with a strong focus on security, embedded systems, cryptography, and smart-card/PKI integration.

• Proven Full Stack Expertise – Several years of hands-on experience, strong skills in Java (Spring Boot), JavaScript/React, microservices architecture, and scripting (Linux shell, Python).
• Adaptability & Problem-Solving – Ability to quickly dive into large-scale legacy projects, work independently on complex engineering challenges, and deliver efficient solutions.

• Professional Communication – Broad technical perspective combined with business-fluent English for effective collaboration in international environments.

• Additional Technical Skills – Advantageous experience with TypeScript, Angular or other FE frameworks, Electron, C#, security/cryptography, embedded development (e.g. smartcard), DevOps across Linux/Windows, plus Docker and AWS.
• Leadership & Mindset – Ownership of complex projects end-to-end, strong communication and teamwork, willingness to mentor juniors, and the ambition to grow into a lead developer role with long-term commitment.

1. Join a highly impactful long-term project with strong growth potential.
2. Take ownership in a modern, international environment with cutting-edge technologies.
3. Contribute actively to building sustainable solutions that make a difference.

Key Facts

• Project Start: asap/September 2025
• Contract Type: Freelancer
• Workload: 100%
• Hourly Rate: 75 EUR
• Location: Fully remote – work from anywhere within the EU - you need EU-work visa or permission
• Language: English
• Duration: 12 months ++ (long-term commitment preferred)