C# Developer (Tactical Tools)

About Phi Partners

Phi Partners is a leading global consultancy specialising in treasury and capital markets technology. With more than 500 professionals worldwide, we are recognised as the largest specialist consultancy dedicated to capital markets technology platforms. For over 20 years, we have supported tier-one financial institutions in delivering complex transformation initiatives, regulatory programmes, and front-to-back platform modernisation projects across global markets. Our technology practice spans front-office tooling, application development, and capital markets systems, placing specialist developers within client engineering teams across a wide range of technologies and delivery contexts.

About the Programme

Phi Partners has been engaged to reinforce the development capacity of a proximity development team at a leading European investment bank's Global Markets technology division. The team - approximately ten developers - builds and maintains lightweight, integrated applications and tools that support trading and operational business users in their day-to-day workflows, including integrations with common productivity tools such as Outlook and Excel. The current programme focus includes the maintenance of existing C# applications, development of new services, and a strategic replacement of legacy WCF components with modern API-based alternatives. The team's production application base is managed collaboratively across multiple locations, making strong written English essential for day-to-day collaboration.

About the Role and Responsibilities

As C# Developer (Tactical Tools), you will join the proximity development team to maintain existing applications and build new lightweight services that serve the bank's trading and operational business users.

Key responsibilities include:

• Maintain and evolve the existing suite of C# proximity applications integrated into business users' daily tooling (Outlook, Excel, and other productivity platforms).

• Develop new applications and services in C#, using the latest language versions and syntax features.

• Lead and contribute to the replacement of legacy WCF components with modern REST API alternatives.

• Create and consume REST APIs; participate in the design and documentation of service interfaces. • Collaborate closely with distributed team members; strong written English communication is essential.

• Apply quality, performance, and security standards throughout the development lifecycle.

• Prepare and execute unit and integration tests; contribute to documentation for future development.

Key Skills

Essential:

• 3+ years of professional C# development experience, with recent exposure to the latest C# language versions and modern syntax.

• Solid SQL skills for data access and integration within application services.

• Strong experience creating and consuming REST APIs; understanding of WCF and its migration to modern API patterns.

• Good level of written and spoken English for effective collaboration within a distributed team.

• Autonomy, attention to quality, and ability to work effectively within a small, collaborative development team.

Desirable:

• Experience with OpenShift, Kubernetes, or Docker container platforms.

• Knowledge of Microsoft Graph APIs for Office 365 and productivity tool integrations.

• Familiarity with Agile delivery practices and sprint-based development.