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
Strong 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
Robust 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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