Senior C# Developer

Project overview

Contract Opportunity | Tier 1 Investment Bank | Canary Wharf

Our client, a Tier 1 Investment Bank based in Canary Wharf, is seeking an experienced C# Developer to join a strategic application modernisation programme. This role sits within a technology team responsible for evolving critical business applications, supporting a transition from Legacy desktop solutions to modern web-based and cloud-enabled platforms.

The successful candidate will work across the full software development lifecycle, contributing to the enhancement of existing applications while helping shape the future-state architecture.

Key Information

Role: Senior C# Developer

Project details

Canary Wharf, London (Hybrid Working)

Contract Length: 6 months Initial Contract

£416 per day (Inside IR35)

Start Date: ASAP

The Programme

This role forms part of a wider transformation initiative focused on:

The successful contractor will work closely with development teams, business stakeholders and architecture functions to deliver high-quality software solutions within a complex enterprise environment.

Key Responsibilities

Required Skills & Experience

Essential

Desirable

Personal Attributes

GCS is acting as an Employment Business in relation to this vacancy.

• Modernising Legacy desktop applications
• Migrating technology platforms from on-premise infrastructure to Azure
• Supporting the transition from desktop-based solutions to web technologies
• Improving application performance, maintainability and scalability
• Delivering new functionality aligned to business and regulatory requirements
• 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 Back End 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
• 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
• Start: ASAP
• Duration: 6 months
• Location: London, UK, GB
• Rate: 50-52 EUR/h