Software Engineer

About the role

Role Overview

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.

Key responsibilities for this role include:

- Support the full software development lifecycle: planning, design, development, testing, deployment, and continuous improvement.

- Build and enhance:

- desktop and embedded user interfaces that are highly usable and tightly integrated with system and device logic

- 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.

- Manage source code and branching strategy, and review teammates' pull requests.

- Collaborate across engineering and with stakeholders to translate technical and operational requirements into reliable, maintainable solutions.

We are ideally looking for someone with the following skills and experience:

- Python (OOP), plus Rust or C++, and modern development practices.

- GUI development experience (Qt, PySide6, QtQuick/QML) and a good eye for usability.

- Exposure to instrument or embedded systems — e.g. high-speed image acquisition; precision sample positioning (piezo/stepper stages); laser-scanning illumination control; automated sample handling (pipetting robots); failure-mode detection and recovery; data quality checks; near-real-time data processing.

- Familiarity with scientific computing and machine learning — NumPy, SciPy, Jupyter, PyTorch, Matplotlib.

- Knowledge of CI/CD (e.g. 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.

Don’t feel you have to tick all the boxes to apply. Our team thrives on shared learning and collective growth.

Why work for Refeyn?

Compensation and core benefits

- We anticipate a base salary of £40,000 to £60,000 for this role, depending on candidate experience

- Hybrid working - minimum 3 days in office

- 25 days annual leave per year in addition to bank holidays