Senior Full-Stack Engineer – .NET, React & AWS

Job Description

We are looking for an experienced Senior Full-Stack Engineer to help design, build and operate a scalable product platform.

You will work across the full application stack, developing responsive user interfaces, secure APIs, business services, data integrations and event-driven cloud components. The role combines modern front-end development using React, TypeScript and Vite with backend engineering using C#, .NET 10, ASP.NET Core, PostgreSQL and AWS.

This role is ideal for an engineer who enjoys solving complex technical problems, contributing to architectural decisions and taking ownership of software from initial design through production operation.

What You’ll Do

• Design, develop and maintain end-to-end product features across the front-end, API, service and data layers.
• Build responsive and maintainable web applications using React, TypeScript and Vite.
• Develop reusable React components and establish consistent front-end development patterns.
• Translate product and user-experience requirements into accessible, reliable and intuitive interfaces.
• Integrate front-end applications with REST APIs, authentication services and asynchronous backend workflows.
• Implement client-side validation, error handling, loading states and secure session management.
• Optimise front-end applications for performance, maintainability and browser compatibility.
• Build scalable backend services using C#, .NET 10 and ASP.NET Core Web API.
• Design RESTful APIs and service interfaces for web applications, internal services and third-party integrations.
• Implement authentication, authorisation and identity-management workflows using Keycloak.
• Develop event-driven and asynchronous processing solutions.
• Design and optimise data-access solutions using Dapper, PostgreSQL and SQL.
• Create and maintain SQL queries, stored procedures, functions and database migrations.
• Work with caching and distributed storage technologies including Valkey and SeaweedFS.
• Apply Clean Architecture and Onion Architecture principles to create modular, testable and maintainable applications.
• Design services for high availability, horizontal scalability, fault tolerance and predictable performance.
• Write unit and integration tests for front-end components, business logic, APIs and infrastructure integrations.
• Participate in architectural reviews, technical design discussions and engineering planning.
• Investigate complex production incidents and implement sustainable corrective actions.
• Improve system reliability through structured logging, monitoring, alerting and distributed tracing.
• Review code and provide constructive technical feedback to other engineers.
• Contribute to technical documentation, coding standards and reusable engineering patterns.
• Maintain CI/CD pipelines and support reliable, repeatable software releases.
• Collaborate closely with product managers, designers, QA engineers, DevOps engineers, data specialists and other stakeholders.

What You’ll Bring

• Strong commercial experience developing applications with C# and .NET.
• Hands-on experience building APIs and services with ASP.NET Core Web API.
• Strong hands-on experience with AWS services and cloud-native architectures.
• Experience implementing identity and access-management solutions with Keycloak.
• Familiarity with Amazon Cognito, including authentication flows, tokens, roles and application integration.
• Deep understanding of Clean Architecture, Onion Architecture and Service-Oriented Architecture.
• Strong SQL skills and practical experience with PostgreSQL.
• Experience developing and optimising stored procedures, functions and complex SQL queries.
• Experience using lightweight data-access technologies such as Dapper.
• Experience designing and developing high-load or business-critical applications.
• Strong understanding of API design, asynchronous processing and distributed-system behaviour.
• Experience writing unit and integration tests using xUnit or NUnit and Moq.
• Strong hands-on experience developing production applications with React.
• Strong proficiency in TypeScript, JavaScript, HTML and CSS.
• Practical experience building and configuring applications with Vite.
• Experience developing reusable, modular and testable React components.
• Strong understanding of React hooks, state management and application composition.
• Experience integrating React applications with REST APIs.
• Experience implementing authenti…