Azure Cosmos DB Developer

Azure Cosmos DB Developer - Financial Markets & Data Platform Transformation Hybrid | Central London (1-3 days per week onsite) 6-Month Initial Contract ASAP Start £460 per day (Inside IR35) We are seeking an experienced Azure Cosmos DB Developer to join a leading global financial markets infrastructure and data organisation on a major transformation programme. This is an exciting opportunity to play a key role in modernising critical application and data engineering platforms, working with cutting-edge Azure technologies, cloud-native architectures, and large-scale data solutions. You'll be responsible for designing, developing, and optimising high-performance Cosmos DB solutions while contributing to enterprise-scale data engineering initiatives across Microsoft Azure and Microsoft Fabric. The Role Working within a highly technical engineering environment, you will help drive the adoption of modern cloud-native solutions and best practices across application development, data engineering, and platform delivery. This position requires a strong understanding of Azure Cosmos DB, distributed computing concepts, and data pipeline development, alongside the ability to collaborate effectively with architects, DevOps teams, and stakeholders across the business. Key Responsibilities

• Develop cloud-native applications leveraging Azure Cosmos DB (SQL API and Mongo API).
• Design efficient NoSQL data models aligned to application and business requirements.
• Optimise Cosmos DB queries, throughput management, and RU consumption.
• Implement effective partitioning, indexing, and consistency strategies.
• Build and maintain robust CI/CD pipelines using GitLab DevOps.
• Develop scalable and performant solutions using Cosmos DB SDKs.
• Integrate Cosmos DB within microservices architectures.
• Design and implement PySpark data pipelines on Microsoft Fabric.
• Utilise Cosmos DB Change Data Feed (CDF) for real-time and event-driven processing.
• Develop automated testing frameworks and maintain unit and integration tests using PyTest.
• Collaborate with engineering, architecture, and DevOps teams to deliver enterprise-scale solutions.
• Ensure solutions adhere to security, governance, and regulatory requirements. Essential Skills & Experience
• Strong hands-on experience with Azure Cosmos DB, including: query optimisation; throughput management; partitioning strategies; indexing optimisation; consistency models
• Proven experience working with Cosmos DB Change Data Feed (CDF).
• Experience integrating and troubleshooting Spark with Cosmos DB CDF.
• Strong technical expertise in PySpark and distributed computing concepts.
• Experience developing and optimising NoSQL data models.
• Proficiency with Azure Cosmos DB SDKs such as: Python; .NET; Java; Node.js
• Strong experience with PyTest and automated testing practices.
• Knowledge of concurrency patterns, scalable application design, and high-performance systems.
• Experience with Git, source control, and CI/CD tooling.
• Excellent problem-solving, communication, and stakeholder management skills. Desirable Experience
• Advanced development experience with: C#, ASP.NET, .NET Core
• Strong object-oriented design and software engineering principles.
• Experience within financial services, capital markets, or highly regulated environments.