Job offer

The Institute of Environmental Science CML at Leiden University is looking for a motivated Junior Research Software Engineer (RSE) with experience in full-stack development, data visualization, and modern software engineering practices to turn scientific insights into reliable and user-friendly software. In this role, you will help design, build, and maintain the next generation of industrial ecology research tools that support sustainability, circular economy analysis and decision making, as well as reproducible science across the institute. You will work closely with researchers to help create dashboards, APIs, and visual analytics that communicate scientific results to academic users, policymakers, and the wider public. Your contributions will directly empower transparent, open, and reproducible research within for sustainability decision making.

What you will do In your role, you will work closely with a Senior Research Software Engineers, Principal Investigators and PhDs to strengthen the scientific software engineering basis of our institute. Specifically, you will be responsible for tasks such as:

• Building and maintaining scientific software, web applications and dashboards for research dissemination and policy communication (e.g., WISE database, Activity Browser, Panorama web-app, ReLab)
• Supporting the development and maintenance of data pipelines and reproducible workflows for environmental databases and analytics.
• Collaborating with researchers to scope features, translate research needs into user-friendly tools, and ensure usability and accessibility.
• Supporting deployment in cloud and/or open environments (e.g., containerized services), working with the senior RSE on infrastructure alignment.
• Promoting good data and software management for FAIR and open science practices, version control (Git/GitHub), testing (pytest), packaging, documentation, etc.

• MSc in computer science, data science, AI, environmental informatics, or related field.
• Good programming skills with Python and JavaScript/TypeScript. Other programming languages are a plus.
• Experience with front-end frameworks (e.g., React) and data visualization (e.g., D3/Plotly).
• Experience building back-end APIs (e.g., FastAPI, Django, Flask) and integrating databases (SQL/NoSQL).
• Experience contributing to open-source projects.
• Familiarity with containerization (e.g., Docker) and reproducibility tools
• Excellent collaboration skills, a service mindset, and enthusiasm for environmental applications and open science

We offer an initial one-year contract, with an option to extend to a permanent contract based on performance, following the pay scale 9 in accordance with the Collective Labour Agreement for Dutch Universities. Salary ranges from € 3.708 to € 5.057 gross per month based on a full-time position.

At our institution, we believe in flexibility and work-life balance! With a full-time position (38 hours per week), you are entitled to 232 vacation hours per year, which is equivalent to 30.5 vacation days (based on a 38-hour work week). If you value flexibility, you have the freedom to adjust your working hours. For example, you could choose to work 40 hours per week, earning extra compensation hours. Alternatively, if you prefer a shorter work week, you can work 36 hours per week by using some of your vacation days to create more time for yourself. You'll work closely with your supervisor to tailor your schedule in a way that suits both your needs and the team's.

In addition, we offer a comprehensive benefits package, including:

• Holiday allowance (8%) and an end-of-year bonus (8.3%)
• An attractive pension scheme with ABP, ensuring your financial well-being both now and in the future
• Extensive options for secondary employment conditions: You can explore options such as sabbaticals, paid parental leave, and the individual choices model, which allows you to exchange leave days and/or salary for benefits like an advantageous sports subscription, bicycle scheme, and childcare options
• Hybrid working options: If your role allows, you can enjoy the flexibility of working from home within the Netherlands
• Home-working allowance: You'll receive a home-working allowance (for both workdays and internet), and the university will provide you with a laptop and support for creating a comfortable home office

Leiden University is situated between Amsterdam (36 km) and The Hague (15 km) and was founded in 1575, making it the oldest university in the Netherlands. It houses around 35,000 students originating from 112 nationalities, facilitated by approximately 8,000 staff. The Institute of Environmental Science (CML) at Leiden University offers a vibrant and supportive community of scientists committed to the challenges of sustainability. CML distinguishes itself for its attention to professional development in coordination with the interests of its scientists. As such, there are plenty of opportunities to learn new skills, expand your knowledge, collaborate across disciplines, and experiment in a friendly environment fully embodying academic freedom across all career levels. The core focus of CML is to perform research and education in the interdisciplinary field of Environmental Sciences. CML focuses on the sustainable use of natural resources and preservation of natural capital and biodiversity. CML has a culture of mutual support and collaboration between researchers. CML has two Departments: Industrial Ecology (CML-IE) and Environmental Biology (CML-EB). Presently, about 150 fte (including postdocs and PhDs) are employed at CML. CML further collaborates with TU Delft and Erasmus University in the Leiden-Delft-Erasmus Centre for Sustainability (LDE-CfS), and with the Naturalis Biodiversity Centre. The Institute of Environmental Sciences (CML) is positioned in the Faculty of Sciences. The Faculty of Science is a world-class faculty where staff and students work together in a dynamic international environment. It is a faculty where personal and academic development are top priorities. Our people are committed to expanding fundamental knowledge by curiosity and looking beyond the borders of their own discipline; their aim is to benefit science and to make a contribution to addressing the major societal challenges of the future. The research carried out at the Faculty of Science is very diverse, ranging from mathematics, information science, astronomy, physics, chemistry and bio-pharmaceutical sciences to biology and environmental sciences. The research activities are organized in eight institutes. These institutes offer eight bachelor's and twelve master's programmes. The faculty has grown strongly in recent years and now has more than 2.800 staff and almost 6000 students. We are located at the heart of Leiden's Bio Science Park, one of Europe's biggest science parks, where university and business life come together.