Senior .NET Developer (Financial Services)

6-Month Contract | $900-$950 per day | Hybrid Working (3 Days in Office) We are seeking an experienced Senior .NET Developer to join a high-performing team delivering modern financial technology solutions. This is an exciting opportunity to work on enterprise-grade APIs and analytics platforms supporting sophisticated pricing, risk, and market data services.

This role will suit an engineer with strong backend development expertise, a passion for clean API design, and experience building scalable, high-performance systems within complex environments.

About the Role

As a Senior .NET Developer, you will be responsible for designing, developing, and maintaining modern REST-based services that underpin critical financial applications. You'll collaborate closely with engineers across .NET, TypeScript, Python, and Excel-based platforms to deliver robust and scalable solutions.

Key Responsibilities

- Design and develop versioned REST APIs using ASP.NET Core and .NET 10
- Integrate pricing, market curve calibration, risk, scenario, and product engines
- Design strongly-typed API contracts and persistent financial domain resources
- Build and maintain integrations with PostgreSQL, reference data services, and external data sources
- Develop background processing and data import services
- Ensure compatibility with shared .NET Standard 2.0 libraries
- Create and maintain unit, integration, API contract, and OpenAPI test suites
- Implement observability solutions including tracing, metrics, diagnostics,



and orchestration using .NET Aspire and OpenTelemetry
- Collaborate with cross-functional teams developing solutions in .NET, Python, TypeScript, and Excel

Required Skills & Experience

- Robust commercial experience with C# and ASP.NET Core
- Proven experience designing and building RESTful APIs
- Solid understanding of dependency injection and modern software architecture principles
- Experience with asynchronous and concurrent programming patterns
- Strong testing background, including unit and integration testing
- Experience working with relational databases, particularly PostgreSQL
- Strong problem-solving skills and ability to work independently in an agile environment

Desirable Experience

- Financial markets or capital markets experience
- Knowledge of quantitative analytics and numerical methods
- Experience building distributed systems and microservices architectures
- Docker containerisation experience
- Azure cloud platform experience
- CI/CD pipeline implementation and automation
- Experience with observability platforms and application monitoring

What's on Offer?

- 6-month initial contract
- $900-$950 per day
- Hybrid working model with 3 days per week in the office
- Opportunity to work on sophisticated financial systems and modern technology stacks
- Collaborative, highly skilled engineering environment
- Potential for contract extension based on project requirements

If you're a strong .NET engineer looking to work on challenging financial technology projects using the latest Microsoft technologies, we'd love to hear from you.

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