Lead .NET Developer

Lead .NET Developer – Hybrid – Up to £700/day Outside IR35 | C# | Azure | Event-Driven Systems | Kafka | Energy Trading We have a unique opportunity for a Lead .NET Developer to join a leading energy trading business. As the Lead .NET/Full Stack Developer, you’ll play a key role in shaping and scaling a high-performance energy trading platform as the business enters its next phase of growth. This includes developing new trading capabilities, integrating with energy markets and external data providers, and expanding a platform that supports critical trading, pricing, and risk processes. You’ll be building on top of a modern, cloud-native platform built with .NET and Azure, designed around API-first architecture and event-driven microservices. The platform supports real-time market data, trading workflows, pricing, position management, and high-volume financial and energy transactions. This is a hands-on technical leadership role where you’ll help drive engineering best practices, contribute to architectural decisions, and mentor developers while remaining close to the code. Working closely with Traders, Quantitative Analysts, Risk, Data, and Platform teams, you’ll help evolve the platform architecture and deliver secure, scalable, resilient, and high-performance distributed systems within a fast-moving energy trading environment. 📍 2 days per week in the office – City of London 💰 Up to £700/day Outside IR35 🗓️ Initial 6-month contract Responsibilities Lead the design and development of high-performance .NET services supporting an energy trading platformBuild and scale event-driven microservices running in AzureDevelop systems supporting trading, pricing, market data, positions, and risk workflowsWork with real-time and high-volume energy market data and trading eventsDrive best practices across architecture, coding standards, observability, performance, and reliabilityWork closely with Traders, Risk, Data, and Product teams to translate trading requirements into robust technical solutionsDesign and develop API-driven integrations with internal systems, market data providers, and external trading platformsMentor and support engineers across the team while contributing hands-on to critical systemsHelp evolve a scalable, distributed architecture capable of handling high-volume, time-sensitive workloadsContribute to improving engineering velocity, delivery quality, platform resilience, and operational performance What we’re looking for Strong experience building production systems with .NET / C#Experience building cloud-native systems in AzureStrong experience with event-driven architectures such as Kafka, Azure Service Bus, Event Grid, or other messaging platformsExperience with Azure Cosmos DB or other distributed NoSQL technologiesProven experience building distributed systems and scalable APIsExperience working within energy trading, commodities trading, financial markets, or other high-performance trading environmentsUnderstanding of market data, trading workflows, pricing, positions, or risk systemsStrong understanding of system design, reliability, concurrency, and performance at scaleExperience designing systems where low latency, throughput, resilience, and data accuracy are criticalAbility to lead technically while remaining hands-on in developmentLead .NET Developer – Energy Trading – Hybrid – £700/day Outside IR35 | C# | Azure | Kafka | Event-Driven Systems | Trading | Market Data