Senior Dotnet Developer

Job Summary

Join Capgemini’s Financial Services Business Unit within the C&CA (Cloud & Custom Applications) practice as a .NET Developer. Guided by our vision to “Consult with Purpose. Continuously Evolve. Architect Tomorrow.”, you will design and deliver high-performance, scalable enterprise applications that drive real business value. This role combines full stack engineering with modern delivery practices, enabling you to contribute to robust, user-focused digital solutions. As a trusted, AI-aware engineer, you will help shape resilient systems while contributing to a future-ready, collaborative engineering culture.

Hybrid working:

The places that you work from day to day will vary according to your role, your needs, and those of the business; it will be a blend of Company offices, client sites, and your home; noting that you will be unable to work at home 100% of the time.

Key Responsibilities:

• Design, develop, and maintain scalable, secure, and high-quality applications using C#, .NET, and ASP.NET Core.
• Build Microservices-based solutions, REST APIs, and service integrations using synchronous, asynchronous, and event-driven communication patterns.
• Implement and support messaging solutions using Azure Service Bus, Kafka, RabbitMQ, or similar technologies.
• Configure and manage API Gateway solutions, ensuring secure, reliable, and governed API access.
• Develop resilient distributed systems using fault-tolerance patterns such as Retry, Circuit Breaker, caching, and Dead Letter Queue handling.
• Apply security best practices including OAuth 2.0, JWT, OpenID Connect, SSL/TLS, and secret management solutions.
• Collaborate with architects, engineers, and business stakeholders to deliver enterprise solutions aligned with business objectives.
• Maintain high engineering standards through unit testing, code reviews, CI/CD practices, and continuous improvement.
• Troubleshoot and resolve complex production issues while optimizing application, API, database, and messaging performance.
• Leverage AI-assisted development tools and practices to improve productivity, quality, and innovation.

Must-Have Skills:

• Strong experience with C#, .NET, ASP.NET Core, and enterprise application development.
• Hands-on experience designing and implementing Microservices, distributed systems, and service-to-service communication using REST, gRPC, and messaging patterns.
• Experience with messaging technologies such as Azure Service Bus, Kafka, RabbitMQ, or similar platforms.
• Strong understanding of API Gateway implementation, Dependency Injection (DI), asynchronous programming, and concurrent application design.
• Knowledge of OAuth 2.0, JWT, OpenID Connect, SSL/TLS, Azure Key Vault (or similar), and secure application development practices.
• Experience implementing resiliency, caching, logging, monitoring, and observability solutions in distributed environments.
• Expertise in SQL, database design, performance tuning, and data management.
• Experience with unit testing frameworks (xUnit, NUnit, MSTest) and applying Clean Architecture, SOLID principles, and modern design patterns.
• Experience working within Agile delivery teams and the full software development lifecycle.
• Strong analytical, problem-solving, communication, stakeholder management, and AI-assisted development skills.
• Good to have : Angular

We are a Disability Confident Employer:

Capgemini is proud to be a Disability Confident Employer (Level 2) under the UK Government’s Disability Confident scheme. As part of our commitment to inclusive recruitment, we will offer an interview to all candidates who:

• Declare they have a disability, and
• Meet the minimum essential criteria for the role.

Please opt in during the application process.

Make It Real (what does it mean for you):

• You’d be joining an accredited Great Place to work for Wellbeing in 2024. Employee wellbeing is vitally important to us as an organisation. We see a healthy and happy workforce a critical component for us to achieve our organisational ambitions.
• To help support wellbeing we have trained ‘Mental Health Champions’ across each of our business areas, and we have invested in wellbeing apps such as Thrive and Peppy.
• You will be empowered to explore, innovate, and progress. You will benefit from Capgemini’s ‘learning for life’ mindset, meaning you will have countless training and development opportunities from thinktanks to hackathons, and access to 250,000 courses with numerous external certifications from AWS, Microsoft, Harvard ManageMentor, Cybersecurity qualifications and much more.
• You will be joining one of the World’s Most Ethical Companies®, as recognised by Ethisphere® for 13 consecutive years. We live our values by making ethical business choices every day. Working ethically is at the centre of our culture at Capgemini, meaning you will be helping to create a future we can all be proud of.

Why you should consider Capgemini:

Growing clients’ businesses while building a more sustainable, more inclusive future is a tough ask. When you join Capgemini, you’ll join a thriving company and become part of a collective of free-thinkers, entrepreneurs and industry experts. We find new ways technology can help us reimagine what’s possible. It’s why, together, we seek out opportunities that will transform the world’s leading businesses, and it’s how you’ll gain the experiences and connections you need to shape your future. By learning from each other every day, sharing knowledge, and always pushing yourself to do better, you’ll build the skills you want. You’ll use your skills to help our clients leverage technology to innovate and grow their business. So, it might not always be easy, but making the world a better place rarely is.

About Capgemini:

Capgemini is an AI-powered global business and technology transformation partner, delivering tangible business value. We imagine the future of organisations and make it real with AI, technology and people. With our strong heritage of nearly 60 years, we are a responsible and diverse group of 420,000 team members in more than 50 countries. We deliver end-to-end services and solutions with our deep industry expertise and strong partner ecosystem, leveraging our capabilities across strategy, technology, design, engineering and business operations. The Group reported 2024 global revenues of €22.1 billion.

Make it real | www.capgemini.com