C# Developer

Location: London, United Kingdom

Salary: £90,000 per annum

Overview

An opportunity for a skilled C# Developer to join a financial services technology team delivering high-performance, secure and resilient systems. You will work across the full software development lifecycle, collaborating with engineering, QA, product and stakeholders to build and enhance solutions used in regulated environments.

Key Responsibilities

• Design, build and maintain backend services and APIs using C# and .NET.
• Develop scalable, low-latency components with a focus on performance, reliability and security.
• Work with relational databases (SQL Server preferred), including schema design, query optimisation and stored procedures where appropriate.
• Integrate with internal and third-party systems using REST and messaging patterns.
• Write clean, testable code; create unit and integration tests and support automated CI/CD pipelines.
• Participate in code reviews, technical design discussions and incident/problem management.
• Contribute to documentation, operational readiness, monitoring and continuous improvement.

Essential Requirements

• Strong commercial experience with C# and modern .NET (.NET 6+), including asynchronous programming and dependency injection.
• Experience building RESTful APIs and service-oriented architectures (microservices beneficial).
• Solid knowledge of SQL and database fundamentals; familiarity with ORM tools (e.g., Entity Framework) and performance tuning.
• Experience with automated testing (xUnit/NUnit/MSTest), mocking and test-driven practices.
• Understanding of secure coding principles, authentication/authorisation (OAuth2/OpenID Connect) and data protection.
• Comfortable with Git, branching strategies and CI/CD (e.g., Azure DevOps, GitHub Actions or similar).
• Strong communication skills and experience working in Agile/Scrum teams.
• Eligibility to work in the UK.

Desirable

• Financial services domain exposure (payments, trading, risk, compliance or core banking).
• Cloud experience (Azure or AWS), containers (Docker) and orchestration (Kubernetes).
• Messaging/event streaming (Kafka, RabbitMQ, Azure Service Bus) and distributed systems patterns.
• Observability tooling (logging, metrics and tracing) and production support experience.

What You’ll Bring

• A pragmatic approach to delivery with attention to quality and detail.
• Ability to work effectively with stakeholders in a regulated, audit-conscious environment.
• A continuous learning mindset and willingness to mentor and share best practice.