Python Developer

End Date

Monday 09 February 2026

£65,385 - £72,650

Flexibility in when hours are worked, Hybrid Working, Job Share

Join us as a Python Developer and help drive automation and financial modelling that transforms Retail Finance. You’ll lead end to end delivery of high performance Python models and tools, turning complex business needs into clean, user friendly solutions. Working with analysts and domain experts, you’ll ship robust, scalable code and deployable artefacts that make a real impact.

You’ll shape our technical direction, contribute to design forums and code reviews, and mentor a Junior Developer along the way. If you love innovation, big datasets, and building the future of finance, this role puts you right at the centre of it!

JOB TITLE:

Python Developer

SALARY: as per pay range

LOCATION:

Leeds, Wellington Place

ADDITIONAL LOCATION(S):
Halifax, Bristol, Cardiff, Newport

HOURS:

Full Time, 35 hours per week

WORKING PATTERN:
Our work style is hybrid, which involves spending at least two days per week, or 40% of our time, at one of our office sites

Do you have a passion for developing Python applications, driving innovation and automation? Do you have experience building financial models? If so, we're eager to meet you!

We’re looking for a dedicated Python Developer to join our Retail Finance Change team and drive real, business-critical transformation—delivering ground breaking financial solutions. You’ll bring curiosity, analytical thinking, and a passion for change as we tackle a strategic backlog of development and optimisation.

We’re on an exciting journey to transform our Group and the way we’re shaping finance for good. We’re focusing on the future, investing in our technologies, workplaces, and colleagues to make our Group a great place for everyone. Including you.

Take ownership of the full delivery lifecycle of Python financial models and automation tools, including design, build, testing, packaging, release, and ongoing support.

Work closely with Business Analysts and domain experts to translate business needs into technical solutions.

Develop performant financial models and automation tools, optimised for use with large datasets.

Develop user-friendly UIs for model execution and reporting using modern frameworks.

Package and distribute models as deployable artefacts, ensuring reproducibility and dependency management.

Ensure code quality and maintainability with thorough unit, integration and system tests.

Actively participate in design forums and peer code reviews, providing and responding positively to constructive feedback.

Provide mentorship and line management for a Junior Python developer.

Share your Python expertise through collaborative learning sessions with members of the team.

Support the design and implementation of robust operating models.

Leverage your expertise to help shape our technical future; ensure we use the best tools and infrastructure available to us.

• Proven track record of Python model development and implementation.

• Understanding of core software development principles.

• Ability to develop complex financial models, optimise for performance and handle large datasets efficiently.

• Experience with common Python tooling and best practices, including:

• Virtual environments.

• Package management (e.g. uv, pip, poetry).

• Source control (e.g., Git/Git Hub) for collaborative development.

• CI/CD pipelines for automated testing and deployment.

• Testing frameworks (e.g. pytest, unittest).

• Code quality (e.g. flake8, black, isort, myp, ruff)

• Documentation tools (e.g., MkDocs, Sphinx) for maintainable technical documentation.

• Excellent communication and presentation skills.

• Passion for learning and staying ahead of the curve.

• Experience with front-end technologies e.g. React.

• Experience with data processing and validation libraries (Polars, Pandera), numerical computing (Num Py, Numba), and API frameworks…