Backend Software Engineer – Database Systems (Oracle/Java)

What you'll do

You will design and evolve complex data models at the heart of CERN’s accelerator control systems, working on the database backend of large-scale, mission-critical applications. Your work will focus on Oracle-based schemas and Java backend services exposing APIs to applications, tightly integrated into full-stack software systems.

Robust and scalable database systems are essential for control, configuration, and operational applications enabling the operation of CERN’s accelerator complex. You will contribute to the evolution of these data-intensive systems, working on long-lived data models and performance-critical access patterns.

You will join a multidisciplinary team and play a key role in building reliable backend solutions aligned with users’ needs, contributing to systems used at the world’s largest particle physics laboratory.

Learn more

Your responsibilities

Interact with stakeholders, including end-users, Product Owners, and infrastructure providers to gather requirements.
Design and implement reliable data models ensuring ACID properties.
Develop and maintain APIs to access and manipulate data using CRUD operations, including interfacing with AI systems.
Analyse integration requirements across multiple technical domains and design and implement robust solutions.
Contribute to all phases of the software development lifecycle, from requirements analysis to deployment.
Provide technical supervision and mentoring to junior software engineers.
Provide day-to-day operational support to a large user community (500+ users).
Propose and contribute to the evolution of systems under your responsibility and beyond.

Still here? Let's make a quick check about

Your profile

Experience developing high-performance relational databases with Oracle and/or PostgreSQL RDBMS.
Experience in the design and evolution of data models in technical domains.
Knowledge of designing and maintaining high-availability, client-oriented APIs, ideally REST- and gRPC-based.
Experience in Java software development using Spring Boot, JPA, and Hibernate.
Application of software quality assurance practices and associated tools.
Use of CI/CD solutions to build, test, and deploy software to production.
Practical experience in the use of PL/SQL is an advantage.
Master's Degree or equivalent relevant experience in the field of Computer Science or a related field.

Your skills

Knowledge of programming techniques and languages.
Design of databases/repositories.
Architecture and design of ICT systems.
Identification and selection of relevant emerging ICT technologies.
Conceptualising, designing and developing user experiences and interfaces.
Works conscientiously and reliably; delivers on promises.
Delivers high quality work on time and fulfils expectations.
Contributes to promoting a positive atmosphere in the team through an optimistic and constructive attitude; addresses issues.
Adopts a pragmatic approach; understands the value of adopting generic rather than gold -plated' technical solutions.
Spoken and written English, with a commitment to learn French.

Ideal start date: 01/09/2026

Contract duration (in months): 60

Grade range: 6

Benchmark job: 200020 - Computing Engineer

Job flexibility: Hybrid

Global Benefits at CERN

A minimum entry-salary of 9236 Swiss Francs per month (tax free), increasing in line with your years of relevant experience.
30 days of paid leave per year plus 2 weeks annual closure.
Coverage by CERN’s comprehensive health insurance scheme (for yourself, your spouse and children), and membership of the CERN Pension Fund.
Family, child and infant monthly allowances depending on your individual circumstances.
A relocation package (installation grant, removal, travel expenses) depending on your individual circumstances.
Possibility to extend your contract up to 8 years + eligibility for indefinite contract tenure.

Let's get you ready

Be sure to meet the eligibility criteria

You are a national of a CERN Member State or Associate Member State. Currently, we cannot consider applications from Pakistani and Lithuanian nationals for positions with a 2026 start date, as the ceiling defined under Article II.5 of the Associate Membership Agreement has been reached.
You have relevant qualifications and professional experience.
If you have previously held a Staff contract at CERN, you will not be eligible for these positions.
Please pay attention to the additional criteria and requirements for this specific position and mentioned above.

You will need these documents to complete your application

Your CV (English or French)
Any document you consider relevant to your application

Your CERNDepartment

The BE department is at the heart of CERN's accelerator complex.

Its mission is to lead the development, construction, and operation of advanced particle accelerators, and to provide cutting-edge technology solutions that enable new discoveries in fundamental physics. Committed to promoting a culture of excellence, creativity and collaboration, individuals from diverse backgrounds contribute to the advancement of science and technology, as well as engaging in scientific education, outreach, and broader knowledge and technology transfer initiatives.

Overview of CERN

Discover a world where the impossible is made possible!

At CERN, the European Organization for Nuclear Research, we are pushing the frontiers of science and technology. Our groundbreaking work brings together not only physicists but also a diverse range of professionals from engineering, technical, scientific, and administrative fields. Together, we foster an environment where innovation and collaboration thrive.

Every day, we face exciting new challenges and opportunities to contribute to cutting-edge research that shapes our understanding of the universe. We meet these challenges through the diverse perspectives within our teams, ensuring every contribution is valued and driving our shared sense of inclusion and purpose. Diversity is a core value of CERN since its foundation, and it remains central to our mission and continued success.

If you are ready to be part of a dynamic, inclusive community pushing the boundaries of knowledge, CERN is the place where your curiosity and skills can thrive. Be part of our mission to uncover what lies at the heart of the universe! TAKE PART!

Ready To apply?

Be prepared with our resources and tips

All good?

Apply now Allow 15 minutes to complete your online application

Still have a doubt ? Here are the most frequently asked questions

What should I expect during my first week at CERN?

Your onboarding at CERN includes a comprehensive induction programme, which starts with an official welcome session at the beginning of each month. In addition, you will receive important information both before and after your arrival to ensure a smooth transition into your new role. This process is designed to help you get acquainted with CERN’s environment, your team, and the tools and systems you’ll be using.
How big would the team be?

The size of the team you'll be working with at CERN depends on the specific role and department. Some teams are small and highly specialized, while others are larger and more interdisciplinary. During the interview process, you'll have the opportunity to learn more about the team structure for the position you are applying for.
What is the working language at CERN?

The working languages at CERN are English and French. However, it is not always mandatory to speak both languages to work at CERN. We offer language training to help you acquiring the other language.
What support does CERN provide for relocation?

CERN does not offer direct assistance with relocation. However, depending on your role and specific criteria, you may be eligible for certain benefits such as an installation allowance and coverage of travel expenses to join CERN. These benefits are designed to help ease the transition when relocating to the Geneva area. For more information, please consult the “Salary, Benefits and Support“ page.
Do I need a visa to work at CERN?

Whether you need a visa to work at CERN depends on your nationality and the duration of your stay. CERN assists with the necessary visa and work permit processes for its employees and visitors. The specific requirements will be communicated to you during the recruitment process.
What would my salary be?

Salaries at CERN are determined by a structured scale. Salaries are based on your role, qualifications, and experience, and are not subject to negotiation. Specific details will be provided as your application progresses. For more information, please refer to the dedicated page.