C++ Software Developer for Distributed Computing (EP-CMD-2025-20-GRAP)

Job Description

Your responsibilities

We are seeking a highly motivated young researcher to join the NextGen Trigger project and contribute to cutting-edge research at the intersection of particle physics and computational science, in collaboration with the CMS experiment at CERN. The CMS Software (CMSSW) is a key application for simulating, reconstructing, selecting, and analyzing physics data from the Compact Muon Solenoid (CMS) experiment.

You will lead efforts to evolve the CMS Software into a distributed application, enabling it to run across multiple nodes and leverage remote accelerators like GPUs and FPGAs with minimal changes to the existing code. Focus will be on minimizing latency and maximizing throughput using high-performance interconnects (InfiniBand, RoCE), RDMA-supported accelerators, and communication libraries like UCX and OpenMPI. These developments will integrate with the CMS High-Level Trigger (HLT) and Data Acquisition (DAQ) systems, emphasizing fault tolerance, minimal downtime, and data loss prevention. This is a unique opportunity to contribute to groundbreaking research at the forefront of particle physics and computational science.

Key Responsibilities:

• Implement a communication library based on Message Passing Interface (MPI) for distributed data management within CMSSW.
• Study and optimize the integration of remote GPUs and accelerators via high-speed network protocols (RDMA) to offload computational tasks efficiently.
• Investigate fault tolerance mechanisms, ensuring the system can detect and recover from failures in a large-scale, heterogeneous computing environment.
• Extend the CMS DAQ to support a distributed HLT application, leveraging modern orchestration technologies (containers, Kubernetes) and implementing a dedicated test system.
• Work well within a team, collaborating with colleagues at CERN and partnering institutes.
• Present your work at prestigious conferences and workshops both at CERN and internationally.

Your profile

Skills

• Strong background in computer science, physics, or a related field.
• Expert C++ programmer. Experience with the CMS software stack is a plus.
• Proficient usage of software development tools (e.g. Github, GitLab) and continuous integration.
• Knowledge of distributed computing approaches, like MPI, RPC, or PGAS is a plus.
• Knowledge of GPU programming and heterogeneous computing architectures is a plus.
• Knowledge of container technology and orchestration systems is a plus.

Eligibility criteria:

• You are a national of a CERN Member or Associate Member State. A limited number of positions are also available to candidates from Non-Member States.
• You have a professional background in Applied Physics (or a related field) and have either:
  • a Master's degree with 2 to 6 years of post-graduation professional experience;
  • or a PhD with no more than 3 years of post-graduation professional experience.
• You have never had a CERN fellow or graduate contract before.

Additional Information

Job closing date: 07.03.2025 at 23:59hrs CET.

Contract duration: 24 months, with a possible extension up to 36 months maximum.

Working hours: 40 hours per week

Target start date: 01-April-2025

This position involves:

• Stand-by duty, when required by the needs of the Organization.
• Work during nights, Sundays and official holidays, when required by the needs of the Organization.
• Shift work.

Job reference: EP-CMD-2025-20-GRAP

Field of work: Applied Physics

What we offer

• A monthly stipend ranging between 6287 and 6911 Swiss Francs per month (net of tax).
• Coverage by CERN's comprehensive health scheme (for yourself, your spouse and children), and membership of the CERN Pension Fund.
• Depending on your individual circumstances: installation grant; family, child and infant allowances; payment of travel expenses at the beginning and end of contract.
• 30 days of paid leave per year.
• On-the-job and formal training at CERN as well as in-house language courses for English and/or French.

About us

At CERN, the European Organization for Nuclear Research, physicists and engineers are probing the fundamental structure of the universe. Using the world's largest and most complex scientific instruments, they study the basic constituents of matter - fundamental particles that are made to collide together at close to the speed of light. The process gives physicists clues about how particles interact, and provides insights into the fundamental laws of nature. Find out more on http://home.cern.

We are on a Quest. A Journey into discovery like no other. Bring your expertise to our unique work and develop your knowledge and skills at pace. Join world-class subject matter experts on unique projects, in a Quest for greater knowledge and deeper understanding.

Begin your CERN Quest. Take Part!

Diversity has been an integral part of CERN's mission since its foundation and is an established value of the Organization. Employing a diverse workforce is central to our success.