Research Software Engineer (Data Assimilation for Environmental Modeling) (m / f / d)

Eawag, the Swiss Federal Institute of Aquatic Science and Technology, is an internationally networked aquatic research institute within the ETH Domain (Swiss Federal Institutes of Technology). Eawag conducts research, education and expert consulting to achieve the dual goals of meeting direct human needs for water and maintaining the function and integrity of aquatic ecosystems.

The Department of Surface Waters - Research and Management ( SURF ) has a vacancy for a

Research Software Engineer (Data Assimilation for Environmental Modeling) (m / f / d)

This position will enhance the accuracy and reliability of operational one-dimensional (1D) lake models in Canton Ticino through the development of a data assimilation framework. The framework will integrate real-time observations with numerical models to improve predictions of lake thermal structure, providing water managers with more precise forecasting capabilities. The project will directly contribute to Alplakes , a research initiative that provides predictions of the lake conditions throughout the European Alpine region and winner of the 2025 Swiss National Prize for Open Research Data.

This is a fixed-term project position with funding for 6 months (100% FTE or proportionally longer at reduced FTE 60% or 80%). While extension is not anticipated, the framework developed will contribute to ongoing operational systems and may lead to future collaboration opportunities. Salary will be commensurate with qualifications and experience, according to ETH Domain guidelines.

We are looking for a motivated early-career research software engineer with a strong foundation in numerical methods, statistics and programming to join our team. The ideal candidate will have experience developing well-structured, documented Python code (ideally as libraries or packages) and a solid understanding of statistical methods, particularly as they relate to data assimilation. While prior knowledge of numerical modeling or limnology is advantageous, enthusiasm for learning and applying data assimilation to real-world environmental challenges is essential. This position offers an excellent opportunity to gain hands-on experience in operational forecasting systems while contributing to impactful open science research.

The successful candidate will take ownership of developing and implementing the data assimilation framework under the supervision of a senior research software engineer. They will be responsible for the complete technical delivery of the project, including :

• Designing and coding the data assimilation system
• Testing and validating the framework against historical data
• Documenting the code and methodology
• Delivering an operational system ready for deployment

The position will be located either at the Eawag office in Dübendorf or Kastanienbaum depending on candidate preference. The preferred starting date is flexible but ideally would be between February and May 2026.

At Eawag , we have a working environment in which people with different experiences, strengths, and perspectives can fully contribute and further develop. Here, you can help us advance! We promote genuine participation, exchange, and mutual understanding. We create structures that enable the compatibility of work and other areas of life, such as care work, and continuously make efforts to reduce barriers.

Do you have specific requirements regarding the application process or the position, or do you need additional information? Talk to us about it-we will be happy to support you with possible flexible workplace, working hours, and job design solutions. For further information please visit our website about Eawag as well as our conditions of employment.

Evaluation of applications starts immediately and continues until the position is filled. Your application should include a letter of motivation and CV (including links to relevant git repositories). References will be requested at the interview stage.

For further information, please contact James Runnalls .

We look forward to receiving your application. Please send it through this webpage, as any other way of applying will not be considered. A click on the button below will take you directly to the application form.

Applications from employment agencies / personnel consultants are not we j4id10017318a j4it0102a j4iy26a