Company Description ⚡️ About Assystem At Assystem, our mission is to accelerate the global energy transition. With over 7,500 Switchers worldwide, we combine engineering expertise, project management, and digital innovation to deliver major infrastructure programmes. In the UK, we’re at the forefront of landmark projects including Hinkley Point C, Sizewell C, and future Small Modular Reactors (SMRs). By joining us, you’ll be contributing to some of the most exciting and important engineering challenges of our time. Why Join the Community of Switchers? At Assystem, you’ll be part of one of the top three largest nuclear engineering companies in the world. Joining us means working in a collaborative and supportive environment where innovation thrives. You’ll be empowered to grow your skills while contributing to cutting-edge projects that have a lasting global impact. ⚠️ Please note: Due to project security requirements, Unfortunately, visa sponsorship is not available for this position. Job Description The Job Mission This hybrid Senior System Integration Engineer role is based in Bristol, with three days in the office and two from home. You will act as the technical and configuration coordinator for effluent treatment systems within the Nuclear Island. You will drive design stability, lead integration activities and support system engineers with multi discipline issue resolution across the wider project. Responsibilities: Defining and cascading system priorities aligned with project milestones Providing technical guidance to system engineers and resolving multi discipline issues Coordinating with layout, civil, safety, electrical, I&C and commissioning teams Tracking progress and escalating blockers to project and Responsible Designer teams Organising and facilitating the team’s participation in relevant committees Challenging optioneering and promoting system design stability before change initiation Ensuring complete and consistent integration of design changes across systems Qualifications Skills Required: Mechanical or Process Engineering degree or equivalent Background in nuclear, heavy industrial process, energy, water treatment or chemical sectors Strong workload planning capability aligned with technical and project KPIs Excellent interpersonal and communication skills with UK and EU based teams Confident coordinating with remote and international engineering groups Able to build positive relationships across complex, multi discipline project environments Additional Information ⚠️ Please note: Due to project security requirements, Unfortunately, visa sponsorship is not available for this position Why Apply? This is your chance to work on a project that defines the future of clean energy in the UK. You’ll join a forward-thinking organisation where your contribution directly supports a safer, more sustainable world. If you’re ready to take on the challenge and grow with your future team, apply today. Benefits include: Hybrid Working Opportunity Flexible working hours ️ Pension scheme (8% company contribution / 4% personal contribution) ️ 25 days’ paid annual leave bank holidays option to buy or sell days Professional fees reimbursed Employee referral scheme Competitive Sick Pay – Support when you need it Income Protection & 3x Salary Death-in-Service Cover Free Digital Gym Access – Expert-led fitness classes 24/7 Employee Support Line – Mental health, financial & legal help We are committed to equal treatment of candidates and promote, as well as foster all forms of diversity within our company. We believe that bringing together people with different backgrounds and perspectives is essential for creating innovative and impactful solutions. Skills, talent, and our people’s ability to dare are the only things that matter !. Bring your unique contributions and help us shape the future