Mass photometry — a technique developed at the University of Oxford for measuring the mass of individual particles in solution with a specialised microscope — is at the heart of what Refeyn does. Since spinning out in 2017, we've grown mass photometry from an academic breakthrough into a technology now widely used in biological research and increasingly adopted across the bioprocessing industry to develop and characterise drugs. Join Refeyn's 10-person software team building the applications behind our mass photometry instruments — from instrument control and automation to data analysis, visualisation, and reporting. You'll work across the full development lifecycle, closely with product, UX/UI, and the wider R&D; team. Support the full software development lifecycle: planning, design, development, testing, deployment, and continuous improvement. automated instrument control, calibration routines, and failure-mode detection tools for analysing measurement data and interpreting results statistically Investigate, debug, and resolve complex software and system issues. Collaborate across engineering and with stakeholders to translate technical and operational requirements into reliable, maintainable solutions. Python (OOP), plus Rust or C++, and up-to-date development practices. precision sample positioning (piezo/stepper stages); laser-scanning illumination control; data quality checks; near-real-time data processing. Familiarity with scientific computing and machine learning — NumPy, SciPy, Jupyter,



PyTorch, Matplotlib. GitHub Actions) and version control with Git. Experience with Jira and Confluence in a hybrid agile/waterfall environment. Familiarity with testing and code-quality tools such as pytest, mypy, and pylint. Hybrid working
- minimum 3 days in office ~25 days annual leave per year in addition to bank holidays ~ Up to 7% employer matched pension contribution ~ Private health insurance plus critical illness cover, income protection and life insurance ~ Annual Company and Individual bonus scheme Refeyn offers YellowNest Nursery Scheme to all employees once probation is passed, and new parents can benefit from up to 17 weeks fully paid maternity, adoption and shared parental leave, 4 weeks fully paid paternity leave, plus an annual allowance for emergency childcare. All employees receive access to Linkedin Learning which offers thousands of courses to support their personal and professional development. We also run frequent training sessions on both hard and soft skills. We firmly believe that there is great strength in building teams with different voices, experiences, perspectives, and backgrounds so that we can continue to share the team workload and enable our customers to succeed, and we welcome applicants from all sections of society to join us on our mission to advance discovery through innovation. First stage Teams interview (30 minutes) Onsite panel interview and site tour (90 minutes)

📌 Software Engineering (Oxford)
🏢 Refeyn
📍 Oxford