Full Stack Engineer (C# Backend / React .NET Front End) - Lorien Impellam

Full Stack Engineer (C# / .NET & React) - Investment Banking

London (Hybrid) | 6-Month Contract | Investment Bank

We are working with a leading global investment bank to hire a hands-on Full Stack Engineer to help build a brand-new, high-impact web application from the ground up.

This is a unique opportunity to take ownership of a greenfield project delivering a real-time web portal for institutional bond issuers and sales teams-providing live market insights and new issuance updates.

The Role

You will play a critical role in designing, developing, and deploying a full-stack web application, taking it from concept through to production.

This role requires someone who can hit the ground running, build the entire development pipeline, and take ownership across the full software lifecycle-not just individual development tasks.

Key Responsibilities
Back-End Development

• Design and build RESTful APIs using ASP.NET Core (6+)
• Develop clean, scalable, and testable C# code
• Manage data access using EF Core, Dapper, or similar
• Implement secure authentication (e.g. Azure AD, JWT)

Front-End Development

• Build modern, responsive UIs using React (18+) and TypeScript
• Integrate components into existing web applications (Angular or similar)
• Apply best practices for performance, accessibility (WCAG 2.1 AA), and UX
• Contribute to development of secure, client-facing portals

Build, CI/CD & Deployment

• Design and implement CI/CD pipelines (Bitbucket, TeamCity or similar)
• Create build processes using MSBuild, npm/yarn, Webpack
• Configure automated unit, integration, and UI testing
• Manage deployments across staging and production environments

Collaboration & Ownership

• Contribute to architectural decisions and code reviews
• Document APIs (Swagger/OpenAPI), deployments, and runbooks
• Mentor junior engineers and promote engineering best practices

What We're Looking For

• Strong experience in C# / .NET and React development
• Proven track record building external client-facing applications or portals
• Experience delivering end-to-end solutions-from development to production
• Strong knowledge of CI/CD pipelines, build automation, and deployments
• Comfortable working in a greenfield environment with high ownership
• A self-starter mindset with the ability to drive delivery independently

Guidant, Carbon60, Lorien & SRG - The Impellam Group Portfolio are acting as an Employment Business in relation to this vacancy.