Python Developer

About The Company

Client Server is recruiting on behalf of a scaling fintech that is transforming how large industrial and commercial organisations buy and manage energy. The company has developed a sophisticated, real-time energy trading platform designed to make complex energy systems more accessible and easier to use. Its technology supports trading, billing, analytics and other data-intensive operations, helping customers make informed decisions in a rapidly evolving energy market.

The business is growing and offers an opportunity to contribute to a platform with meaningful commercial impact. You will join a collaborative engineering environment where people share ideas, discuss technical options and help shape decisions as the product and organisation continue to develop.

About The Role

Client Server is seeking a Senior Python Developer / Backend Software Engineer to help build and evolve the backend systems behind the company’s energy trading platform. This is a hands-on position for an experienced engineer who enjoys working across software development and data engineering in complex, data-rich environments.

You will design and develop resilient, modular backend services, APIs, data models and data flows. Your work will connect systems and information across PostgreSQL, Amazon Redshift, analytics layers and customer-facing applications, supporting reliable trading, billing and reporting capabilities. You will also contribute to technical discussions and decisions, helping the team deliver maintainable solutions as the platform scales.

The role is remote-first, with the flexibility to work from home full-time. The team meets in London approximately once per quarter, with travel paid for. Applicants must be based in the UK and have the right to work in the UK. The salary is up to £90,000, depending on experience.

Qualifications

You will bring strong software engineering experience across the full development lifecycle, from understanding requirements and designing systems through to implementation, testing, deployment and ongoing improvement. You should have substantial backend development experience with Python, along with practical experience building REST APIs and microservices.

A good understanding of AWS is important, including experience with Amazon Redshift. You should also be comfortable working with PostgreSQL and have experience with data pipelines, ETL processes, data modelling and dbt. Familiarity with event-driven systems, LLMs and agentic programming is relevant to the work.

Experience in fintech, payments, ecommerce or another high-throughput environment would be valuable. Above all, you should be able to work effectively with complex data and systems, communicate clearly, and collaborate with colleagues across technical discussions and delivery.

Responsibilities

Design, develop and maintain backend services in Python that support the energy trading platform. Build and improve REST APIs and microservices, with a focus on reliability, scalability, security and maintainability. Create and evolve data models and data flows across PostgreSQL, Redshift and analytics systems, ensuring information is useful and dependable for trading, billing and reporting.

Contribute to data engineering work, including ETL processes and pipelines, and help strengthen the platform’s handling of high-volume, time-sensitive information. Take part in technical planning, review design options and share informed recommendations. Work closely with team members to deliver changes, investigate issues and continuously improve the quality of the software and data infrastructure.

Benefits

The position offers a salary of up to £90,000 and remote-first working, with occasional, paid team meetups in London. You will have the opportunity to take on technically challenging work, contribute to an impactful product and grow your career as the company expands. The collaborative environment also provides scope to influence engineering decisions and help shape an evolving platform.

Equal Opportunity

Client Server is committed to fair and inclusive recruitment. Applicants will be considered on the basis of their relevant skills, experience and ability to perform the role. We welcome applications from people with diverse backgrounds and do not tolerate discrimination in the recruitment process. Reasonable adjustments can be discussed to support candidates throughout the application and interview process.