Big Data Software Engineer

What you’ll do

Your responsibilities

• Drive the evolution of the CERN Accelerator Archival system (NXCALS).
• Design and develop the core components of the system, including ingestion pipelines (ETL), metadata services, data compaction mechanisms, data extraction algorithms, and APIs.
• Collaborate with different user communities to define and promote best practices for using NXCALS in the development of control applications for the CERN Control Centre.
• Work closely with the CERN IT department to select and validate evolution of the underlying storage technologies (e.g. HDFS, ClickHouse).

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Your profile

• Extensive experience in Java development using the Spring ecosystem.
• Solid knowledge of big-data technologies, including Hadoop, HDFS or Apache Ozone, HBase or ClickHouse, Apache Spark, and Kafka.
• Working knowledge of Python, including SDK development and PySpark.
• Proven experience with modern software engineering practices, including quality assurance, CI/CD, and DevOps methodologies.

Your skills

• Knowledge of programming techniques and languages (java and Python).
• Architecture and design of ICT systems.
• Identification and selection of relevant emerging ICT technologies.
• Conceptualising, designing and developing user experiences and interfaces.

Employment conditions

• A valid driving licence.
• Stand-by duty, when required by the needs of the Organisation.

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 CERN Department

of CERN

Ready To apply?

Be prepared with our resources and tips

• Our Hiring Process
• Life at CERN
• Tips for your Application
• Working at CERN
• What happens after you apply?
• More about CERN

All good?

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.