Principal Python Developer

Principal Python Developer – Data Platforms (x4 roles) - London (1–2 days onsite, hybrid) - Inside IR35 negotiable We are seeking multiple Principal Python Developers to join a major programme building a new data platform in AWS. These roles require strong expertise in Python development within financial services in financial market data. You will play a senior, hands-on role in designing and developing scalable data solutions, working with Spark, AWS, and Aurora PostgreSQL to deliver a high-performance, cloud-native data platform. Key Responsibilities • Design, build, and optimise data-driven solutions using Python in a financial markets environment • Develop and maintain distributed data pipelines using Spark and AWS-native services • Work with Aurora PostgreSQL and other AWS data services for storage, querying, and analytics • Integrate and process financial market data feeds (transactions, market/FX data, asset management systems) • Contribute to the design and delivery of a new AWS-based data platform, ensuring scalability and performance • Collaborate with data engineers, architects, and product teams to align technical delivery with business needs • Apply best practices in testing, CI/CD, and Agile delivery methodologies Skills & Experience Required • Proven experience as a Python Developer with a focus on data platform development • Strong expertise in financial markets data (transaction feeds, private banking, asset management, trading platforms, FX) • Hands-on experience with Apache Spark for distributed data processing • Proficiency with Aurora PostgreSQL • Strong working knowledge of AWS cloud services, especially for data engineering and platform builds • Experience delivering in complex, data-intensive environments • Excellent problem-solving skills, with ability to operate as a senior/principal engineer in Agile teams