Development Team Lead - .NET

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 65 countries across EMEA, North America, Latin America and Asia Pacific. We employ 25,000 people globally, more than half located in Asia Pacific. LSEG’s ticker symbol is LSEG.

OUR PEOPLE:

People are at the heart of what we do and drive the success of our business. Our values of Integrity, Partnership, Excellence and Change shape how we think, how we do things and how we help our people fulfil their potential. We embrace diversity and actively seek to attract individuals with unique backgrounds and perspectives. We break down barriers and encourage teamwork, enabling innovation and rapid development of solutions that make a difference. Our workplace generates an enriching and rewarding experience for our people and customers alike. Our vision is to build an inclusive culture in which everyone feels encouraged to fulfil their potential.

We know that real personal growth cannot be achieved by simply climbing a career ladder – which is why we encourage and enable a wealth of avenues and interesting opportunities for everyone to broaden and deepen their skills and expertise. As a global organisation spanning 65 countries and one rooted in a culture of growth, opportunity, diversity and innovation, LSEG is a place where everyone can grow, develop and fulfil your potential with meaningful careers.

JD for Development Team Lead (.NET)

Position Overview

The Development Team Lead (.NET) is responsible for providing hands‑on technical leadership, mentoring, and delivery oversight for a team building enterprise applications on the Microsoft .NET platform. This role blends deep .NET expertise with people leadership, Agile delivery, and cross‑functional collaboration. The Team Lead works closely with Product, QA, DevOps, Architecture, and Delivery to ensure consistent, predictable, and high‑quality delivery.

This role will play a key leadership role in the modernization of legacy .NET and WCF-based platforms, helping drive the transition to cloud-ready ASP.NET Core APIs, microservices, and Azure-native architectures.

Key Responsibilities

Technical Leadership

• Lead the design and development of applications using C#, VB.NET, ASP.NET Core, ASP.NET MVC, Web API, LINQ, and related .NET technologies.
• Guide modernization of legacy VB.NET, WCF, and .NET Framework applications and services into modern C#, ASP.NET Core, and .NET 8+ API architectures where appropriate.
• Define and lead migration strategies for legacy WCF/SOAP services, including service decomposition, API design, security modernization, backward compatibility, and transition to RESTful and event-driven architectures.
• Provide technical leadership for both the ongoing enhancement of existing WCF-based applications and the strategic modernization of those platforms to ASP.NET Core and cloud-ready architectures.
• Evaluate and implement modern integration patterns using REST APIs, microservices, Azure Service Bus, and cloud-native services as part of application modernization initiatives.
• Perform and enforce high‑quality code reviews, ensuring adherence to coding standards, clean architecture, and SOLID principles.
• Break down complex technical requirements into well‑scoped stories and tasks.
• Work with Architects to align on technical patterns, integration approaches, and long‑term platform direction.

People Leadership & Coaching

• Provide day‑to‑day support, mentorship, and coaching to developers across varying experience levels.
• Foster a positive, inclusive culture centered on learning, ownership, and accountability.
• Conduct regular 1:1s and support career development, skills progression, and performance management.

Agile Delivery & Planning

• Lead sprint planning, backlog readiness, estimation, and throughput optimization.
• Facilitate daily stand‑ups, reviews, and retrospectives; remove team impediments rapidly.
• Coordinate dependencies with QA, DevOps, and other teams; ensure release readiness and change control.
• Partner with the Delivery Manager (or act in that capacity where needed) to maintain predictable sprint throughput and reliable release timelines.

Quality & Reliability

• Ensure strong testing practices: unit testing (xUnit/NUnit/MSTest), integration testing, API testing, and automation support and high code coverage targets.
• Collaborate with QA to embed quality in the workflow; drive shift‑left testing practices.
• Validate that applications meet non‑functional requirements such as performance, resilience, and security.
• Collaborate with DevOps to improve CI/CD pipelines, environment stability, and release automation.

System & Application Ownership

• Provide technical leadership for legacy service modernization initiatives, including assessment, refactoring, migration planning, risk management, and production rollout of WCF-to-.NET Core API transformations.
• Troubleshoot and resolve complex issues across environments (DEV/QA/UAT/PROD).
• Lead root cause analysis for production incidents and identify long‑term fixes.
• Monitor application health using Application Insights, logging frameworks, and dashboards.

Cross‑Functional Collaboration

• Partner with Product Owners to refine user stories, clarify requirements, and provide estimates.
• Work closely with DevOps for CI/CD enhancements and infrastructure needs (Azure preferred).
• Collaborate with QA Lead, Architecture, and Security teams to ensure compliance with standards.

Qualifications

Required

• 8+ years of professional software development experience with .NET Framework, .NET Core, and enterprise application development.
• 2+ years in a people leader role.
• Strong expertise in C#, with hands-on experience developing, enhancing, supporting, and modernizing applications built on VB.NET, WCF, and the .NET Framework. Experience migrating legacy services to ASP.NET Core and modern API architectures is required.
• Hands-on experience designing, developing, supporting, and modernizing WCF/SOAP services, including execution of WCF-to-ASP.NET Core Web API migration initiatives, service contract analysis, authentication modernization, API versioning, and integration modernization.
• Strong understanding of enterprise integration patterns, including SOAP, REST, messaging, service-oriented architecture (SOA), and microservices.
• Experience maintaining and enhancing enterprise applications built on WCF, SOAP, and .NET Framework, including troubleshooting, performance tuning, and delivery of new business functionality.
• Experience building REST APIs, microservices, or modular applications using ASP.NET Core/Web API.
• Proficiency with Git, CI/CD pipelines (Azure DevOps/GitHub Actions), unit testing frameworks, and design patterns.
• Experience working in Agile environments (Scrum/Kanban) with strong facilitation skills.
• Demonstrated ability to lead teams, influence architecture, and deliver complex initiatives.
• Excellent communication, facilitation, and problem‑solving skills.

Preferred

• Experience in a multi‑team environment with shared services (QA, DevOps, Architecture).
• Experience with Microsoft Azure services including API Management, App Services, Azure Functions, Service Bus, Key Vault, and Application Insights.
• Experience modernizing monolithic or service-oriented applications into microservices or cloud-native architectures.
• Experience using modernization tools and frameworks such as .NET Upgrade Assistant, migration assessment tools, and automated code conversion utilities.
• Familiarity with observability (logs, metrics, tracing) and performance tuning.
• Exposure to relational and NoSQL data stores, messaging, and event‑driven patterns.
• Exposure to DevOps concepts such as IaC (Bicep, ARM, Terraform).
• Certifications such as PSM I/II, CSM, PMI‑ACP, or Azure Developer/Architect certifications.

Career Stage:

Senior Associate

London Stock Exchange Group (LSEG) Information:

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.