Full-stack Developer

Full Stack Developer

Full Time

Vilnius

Are you ready to shape the future with your skills? Do you excel at transforming complex information into clear solutions? Join us in contributing to tomorrow’s technology landscape!

We are looking for a skilled Full-Stack Developer with a strong end-to-end mindset and a clear focus on user experience and operational reliability to join our growing digital team in Vilnius (location is fixed). As a Full-Stack Developer in collaboration with our Data Scientists, you will turn new AI capabilities into scalable, production-ready applications. You will build secure backend services and intuitive user interfaces that integrate AI into real business value. Working closely with AI, data, cloud, and various business teams, you will ensure these solutions are reliable, explainable, and deliver measurable value.

Our systems span operational tools, decision-support platforms, and AI-enabled applications. You will work across the full lifecycle; from understanding user needs, to implementation, testing, deployment, and ongoing improvement, in close collaboration with solution owners, data specialists, and domain experts.

On a day-to-day basis, you will:

• Design, develop, and maintain full-stack applications with a strong focus on usability, reliability, and functional correctness.
• Build and maintain robust Python-based backend services, APIs, and integrations.
• Develop intuitive and responsive front-end user interfaces using modern web technologies (e.g. JavaScript – React).
• Work closely with our service manager and key stakeholders to understand workflows, pain points, and priorities, translating these into effective technical solutions.
• Implement validation, testing, and monitoring to ensure systems behave predictably and changes do not negatively impact users.
• Deploy applications in a controlled and repeatable manner, even in the absence of fully formalised release pipelines.
• Contribute to systems involving data, AI and machine learning, selecting and integrating appropriate platforms and frameworks where they add real value.
• Improve existing solutions through refactoring, performance tuning, and incremental enhancements based on user feedback and in close collaboration with the service manager.
• Collaborate effectively with colleagues across disciplines while maintaining the ability to work independently and take ownership of outcomes.

Your skills. Our team. Together we design the future.

The first step to success in this role is that you are eager to collaborate with the people around you, whether they are colleagues, partners or customers. Developing ties with others is something you do by acting respectfully and delivering on your promises. And you never get set in your ways but keep exploring new insights and ways to improve.

We believe you will thrive in this position if you:

• Take ownership and work effectively independently within a collaborative environment.
• Think laterally and strategically about how systems should function end-to-end, not just how individual components are built.
• Balance technical ambition with practicality, prioritising reliability and user value.
• Are comfortable navigating ambiguity and shaping solutions where processes are still evolving.

In addition, you will have:

• Bachelor’s or Master’s degree in Computer Science, Software Engineering, or a related field (or equivalent practical experience).
• Strong experience with Python for backend development.Experience with modern front-end frameworks (e.g. React or similar).
• Solid understanding of API design, data models, and integration patterns.
• Experience deploying and operating applications in production environments.
• Practical knowledge of testing strategies, including unit, integration, and user-focused validation.
• Familiarity with cloud platforms (Azure preferred; AWS considered a plus).
• Familiarity with Infrastructure as Code and containerised deployment practices, including tools and platforms such as Terraform, Docker, and Kubernetes (AKS), in production environments.
• Experience working with or integrating AI and ML solutions, and the judgement to know when these are appropriate.
• Good understanding of version control, documentation, and collaborative development practices.
• Strong communication skills in English, able to work effectively with both technical and non-technical colleagues.

A place to work and so much more

At COWI, we work together with our customers to shape a sustainable and livable world. We do it by applying our knowledge and curiosity – and sometimes even our courage – to create the solutions the world needs today to enable a better tomorrow. We support our customers’ transition towards increased sustainability. We strive to lead by example by embedding environmental management, social responsibility, and good governance into our business practices and the options we provide to our customers.

We value differences and development and cultivate an environment of belonging and having fun. Because that is what brings out the best in you, at work and at home.

With offices primarily located in the Nordic region, the UK, North America and India, we are currently more than 7,500 people who bring their skills in engineering, architecture, energy and environment into play.

We also offer:

• Private health insurance after the probation period
• Accident insurance from the first day of your employment
• Hybrid way of working
• 1 extra day off after birthday
• Other benefits, such as: new and modern office space, various COWI partner discounts and offers, social initiatives and corporate events

The anticipated salary range for this position is between 3300 to 4400 EUR (before taxes). However, we believe in your individuality and professional capability, therefore the final offer will be based on your skills and experience.

Got more questions?

If you have any questions about the role or what we have to offer, please reach out to our Talent Acquisition Specialist, Preetika Suri at pksu@cowi.com.

Get to know us even better at our website, www.cowi.com, where you can learn more about our projects, our strategy, what we want to accomplish and what life is like at COWI.

Diversity is fundamental to COWI, inclusion is key

We are committed to creating a respectful and fair work environment where all employees have a sense of belonging and equitable opportunities to thrive and grow. We ensure that our leaders are role models for inclusive leadership by cultivating a culture where diverse perspectives and thoughts are seen as strengths. And we take diversity and inclusion into account in all relevant decisions and processes and when setting teams and fora. We do it because it is part of our values and because it is simply the right thing to do.