Senior Full Stack Developer

Location: Newcastle upon Tyne

Fantastic opportunity to join a thriving Financial Services business.

What is the role?
As a Senior Full Stack Developer, you will lead technically complex features, projects and services where requirements, architecture or implementation approaches are uncertain. You will turn ambiguous business problems into reliable technical outcomes across the firm's real-time, business-critical trading platforms and guide other engineers contributing to the work.

You will provide independent technical leadership within the relevant domain, resolving ambiguity, making significant design decisions and coordinating other contributors while escalating decisions with material product-wide, regulatory, security or architectural consequences. The role combines hands-on work across C#/.NET, React, Type Script, SQL Server, APIs and integrations with strong attention to security, resilience, performance, operability and long-term maintainability.

You will act as a trusted technical adviser to Product and QA, work with Support on significant operational issues, and mentor and guide engineers contributing to complex work. The business offers the opportunity to solve difficult technical challenges across distributed, event-driven and real-time derivatives and structured-products trading systems.

Key Responsibilities
Design and Implementation

* Deliver owned work from clarification and design through implementation, testing, release and production operation.

* Design and implement maintainable changes across C#/.NET services, React and Type Script user interfaces, HTTP APIs, integrations and SQL Server databases.

* Apply proportionate engineering design and document material decisions, assumptions and trade-offs.
Quality and Testing

* Write and maintain appropriate unit, integration, API and front-end automated tests.

* Use Git, Azure Dev Ops, build pipelines and CI/CD processes safely and consistently.
Production and Operational Support

* Diagnose application, integration and data issues using logs, monitoring, debugging and data analysis.

* Improve monitoring, alerting, runbooks, documentation and operational readiness.
Collaboration

* Work with Product and Business Analysis to clarify outcomes, priorities and acceptance criteria.

* Work with QA to define suitable coverage and with Support to investigate production issues.

* Participate in design discussion and provide clear, constructive code-review feedback.

* Communicate progress, dependencies, risks and blockers clearly and early.
Technical Improvement

* Identify technical debt, reliability risks and proportionate improvements to tools and practices.

* Use approved AI-assisted engineering tools responsibly and remain accountable for the result.
Coaching and Leadership

* Lead complex changes from discovery and technical analysis through production operation.

* Mentors and guide engineers contributing to complex work.
Required Skill Set
They primarily develop and support real-time trading systems using the technologies below:

* C# and .NET

* Type Script and React

* SQL Server and Entity Framework

* HTTP APIs and integrations

* RabbitMQ and SignalR

* Azure Dev Ops and Azure services
Essential

* Deep practical experience designing, building and supporting production software using C# and .NET.

* Strong full-stack capability across React, Type Script, SQL Server and HTTP APIs.

* Strong knowledge of object-oriented design, relational data modelling and automated unit, integration and front-end testing.

* Experience delivering complex changes through Git-based source control, code review, Azure Dev Ops and CI/CD pipelines.

* Ability to design services, APIs and integrations and reason about distributed, event-driven and real-time behaviour.

* Strong capability in observability, diagnostics, incident investigation and failure-mode analysis.

* Demonstrated ability to resolve ambiguity, make significant technical decisions and lead complex work without formal authority.

* Understanding of security, performance, resilience, operability, data integrity and long-term maintainability.

* Ability to mentor engineers and coordinate contributors across complex delivery.

* Ability to explain commercial, operational and technical trade-offs to Product, QA, Support and engineering stakeholders.
Desirable

* Experience delivering or operating trading platforms, financial-services systems or other regulated, business-critical software.

* Substantial experience with real-time, high-availability, low-latency or event-driven systems.

* Strong practical…