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Randstad Logo Randstad · IT - Software Development

Senior C# / .NET Developer

United Kingdom, London 550.00 - 585.00 GBP / Day · Job Posted June 29, 2026
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Job Description

A leading global financial services and asset servicing institution is seeking an experienced Senior C# / .NET Developer to join a business-critical technology team in London. This role focuses on designing, building, and supporting high-performance platforms for the firm's financing-related businesses, with a primary emphasis on Securities Lending and Repo workflows.

Job Responsibility

Designing, building, and supporting high-performance platforms for the firm's financing-related businesses, with a primary emphasis on Securities Lending and Repo workflows

Requirements

  • Strong hands-on expertise in C# and .NET / .NET Core
  • Deep understanding of Object-Oriented Programming (OOP) and architectural design principles
  • Proven experience building and implementing REST / JSON APIs
  • Solid experience with relational databases (e.g., SQL Server)
  • Familiarity with unit/integration testing and automated CI/CD pipelines
  • Proven background in Financing platforms, specifically Securities Lending, Repo, or Collateral/Margin management
  • Strong general knowledge of financial markets, with a specific focus on equities and bonds
  • Prior exposure to complex, highly regulated capital markets or financial services environments

Nice to have

  • Experience with cloud platforms (AWS / Azure)
  • Exposure to messaging technologies like Kafka
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