Lead Software Engineer (C#)

About Us:LSEG (London Stock Exchange Group) is more than a diversified global financial markets infrastructure and data business. We are dedicated, open-access partners with a dedication to excellence in delivering the services our customers expect from us. With extensive experience, deep knowledge and worldwide presence across financial markets, we enable businesses and economies around the world to fund innovation, manage risk and create jobs. It’s how we’ve contributed to supporting the financial stability and growth of communities and economies globally for more than 300 years. Through a comprehensive suite of trusted financial market infrastructure services – and our open-access model – we provide the flexibility, stability and trust that enable our customers to pursue their ambitions with confidence and clarity!LSEG is headquartered in the United Kingdom, with significant operations in 70 countries across EMEA, North America, Latin America and Asia Pacific. We employ 25,000 people globally, more than half located in Asia Pacific.Role Summary:We’re looking for a seasoned engineer who thrives on ownership, delivers with consistency, and thinks like a product builder-not just a coder. You’ll play a key role in shaping technical decisions, supporting less-experienced teammates, and freeing the lead engineer from low-level implementation details through reliable execution.What You’ll Be Doing:Design, build, and optimize high-performance .NET applications with a heavy focus on multithreading and asynchronous programming. Work with SQL Server to create efficient, scalable database solutions. Build and maintain services and infrastructure in Azure. Support and mentor junior developers, offering technical guidance and code review. Collaborate closely with the product team and think deeply about end-user experience and business impact. Take initiative on technical improvements, troubleshooting, and system reliability. What You’ll Bring:Must-Have SkillsStrong expertise in .NET with deep experience in multithreading and async patterns - you understand concurrency, race conditions, locking, and performance tuning. Solid SQL Server skills, including query optimization, indexing strategies, and stored procedures. Hands-on Azure experience - App Services, Functions, Service Bus, storage, or related cloud components. 5+ years of professional engineering experience with a track record of delivering production systems. Nice-to-Have SkillsBasic Angular knowledge for full-stack collaboration and UI integration. CI/CD pipelines (Azure DevOps, GitHub Actions, etc.) for smooth delivery and deployment automation. Terraform or similar IaC tools for provisioning and managing cloud environments. Soft Skills We ValueOwnership attitude - someone who picks up problems and sees them through. Proactiveness and initiative - you anticipate needs rather than waiting for instructions. Product-focused thinking - your work reflects the end user’s reality. Dependability - a great teammate who others can trust and who helps maintain a healthy, collaborative engineering environment. Join us and be part of a team that values innovation, quality, and continuous improvement. If you're ready to take your career to the next level and make a significant impact, we'd love to hear from you.LSEG is a leading global financial markets infrastructure and data provider. Our purpose is driving financial stability, empowering economies and enabling customers to create sustainable growth.Our purpose is the foundation on which our culture is built. Our values of Integrity, Partnership, Excellence and Change underpin our purpose and set the standard for everything we do, every day. They go to the heart of who we are and guide our decision making and everyday actions.Working with us means that you will be part of a dynamic organisation of 25,000 people across 65 countries. However, we will value your individuality and enable you to bring your true self to work so you can help enrich our diverse workforce.We are proud to be an equal opportunities employer. This means that we do not discriminate on the basis of anyone’s race, religion, colour, national origin, gender, sexual orientation, gender identity, gender expression, age, marital status, veteran status, pregnancy or disability, or any other basis protected under applicable law. Conforming with applicable law, we can reasonably accommodate applicants' and employees' religious practices and beliefs, as well as mental health or physical disability needs.You will be part of a collaborative and creative culture where we encourage new ideas. We are committed to sustainability across our global business and we are proud to partner with our customers to help them meet their sustainability objectives. Our charity, the LSEG Foundation provides charitable grants to community groups that help people access economic opportunities and build a secure future with financial independence. Colleagues can get involved through fundraising and volunteering.LSEG offers a range of tailored benefits and support, including healthcare, retirement planning, paid volunteering days and wellbeing initiatives.Please take a moment to read this privacy notice carefully, as it describes what personal information London Stock Exchange Group (LSEG) (we) may hold about you, what it’s used for, and how it’s obtained, your rights and how to contact us as a data subject.If you are submitting as a Recruitment Agency Partner, it is essential and your responsibility to ensure that candidates applying to LSEG are aware of this privacy notice.