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# Senior C# Developer

- **Company:** GCS Ltd
- **Location:** London, UK
- **Experience:** Expert
- **Salary:** £80,350.0
- **Contract:** Temporary contract
- **Skills:** Clean Code Principles, ASP.NET, JavaScript (Programming Language), .NET Framework, Application Programming Interfaces (APIs), Software Applications, Microsoft Azure, Business Software, C Sharp (Programming Language), Cloud Computing, Code Review, DevOps, Windows Presentation Foundation, Oracle (Applications), Standard Sql, SQL Stored Procedures, SQL Databases, Windows Forms, ReactJS, Backend, Solid Principles, Legacy Systems
- **Published:** November 1, 2026
- **Apply:** https://www.adzuna.co.uk/jobs/details/5946829024

## About the Role

* Strong commercial experience developing applications using C#/.NET
 * Proven expertise with WPF or WinForms
 * Strong SQL or Oracle development skills
 * Understanding of software design principles and development best practices
 * Experience working within complex enterprise environments
 * Experience working with Azure
 * Experience with JavaScript
 * Exposure to React
 * Experience contributing to application modernisation programmes
 * Knowledge of Azure cloud technologies
 * Experience within Financial Services, Investment Banking or Capital Markets environments
 * Strong analytical and problem-solving skills
 * Excellent communication and stakeholder management abilities
 * Ability to work independently in a fast-paced environment
 * Collaborative mindset and willingness to mentor junior developers
 * Comfortable balancing support of legacy systems alongside modernisation initiatives

## Description

* Develop and maintain enterprise-grade applications using C#
 * Enhance and support existing WPF and WinForms applications
 * Contribute to the migration of desktop applications towards web-based architectures
 * Build and integrate APIs and backend services
 * Write efficient SQL queries and stored procedures
 * Collaborate with business analysts, architects and end users to understand requirements
 * Participate in code reviews and promote development best practices
 * Troubleshoot production issues and contribute to continuous improvement initiatives
 * Support the adoption of Azure technologies as part of the broader cloud transformation strategy

Technologies:

 * Azure
 * Backend
 * C#
 * Cloud
 * Support
 * JavaScript
 * Oracle
 * React
 * SQL
 * WPF
 * Web
 * ASP.NET
 * DevOps, We are supporting a Tier 1 Investment Bank based in Canary Wharf with a strategic application modernisation programme. This contract opportunity is for a Senior C# Developer working in a hybrid setup on a 6-month initial contract, paying £416 per day inside IR35 with an ASAP start. You will join a technology team evolving critical business applications, helping transition legacy desktop solutions to modern web-based and cloud-enabled platforms while working closely with development teams, business stakeholders and architecture functions in a complex enterprise environment.