Job Description:

C# Senior Software Developer - Onsite 

My client is seeking a talented C# Senior Software Developer to join their Preston-based team. This role offers an exciting opportunity to lead projects, mentor junior developers, and work on high-impact, secure banking solutions. You will be a key contributor to web portal and API development, ensuring performance, security, and reliability in a dynamic environment.

This role is ideal for developers with strong technical expertise who are looking to grow into leadership or team management responsibilities.

Key Responsibilities

• Develop and maintain web portals using ASP.NET MVC / .NET Core
• Design and integrate REST APIs with internal and third-party services
• Implement secure authentication mechanisms (JWT, OAuth2, API Keys)
• Connect applications to relational databases using Entity Framework Core (DbContext, LINQ, Migrations)
• Debug and trace request flows from UI → Controller → API → Database → Response
• Maintain and publish API documentation via Swagger / OpenAPI
• Ensure API security, reliability, and performance (error handling, retry logic, logging, timeouts, CORS)
• Collaborate with database, infrastructure, and QA teams for portal and API releases
• Participate in code reviews, version control, and CI/CD deployment workflows

Required Technical Skills

• C# (strong proficiency)
• ASP.NET MVC or .NET Core Web API
• MVC concepts: Routing, Controllers, Filters, Middleware, Model Binding, Dependency Injection
• Entity Framework Core (DbContext, DbSet, OnModelCreating, LINQ) and ADO.NET/Raw SQL experience
• MS SQL Server or MySQL database experience
• HTML5, CSS3, JavaScript
• REST API expertise and integration (HttpClient, RestSharp, JSON serialization/deserialization, CORS, HTTPS, API security)
• Git version control and CI/CD workflows (Azure DevOps, GitLab CI preferred)
• Hosting experience with IIS or Kestrel
• Docker basics (preferred but not mandatory)

Preferred/Bonus Skills

• Experience with fintech or payments API integration
• Cloud services (Azure, AWS) hosting basics
• Webhooks and event-based APIs
• Structured logging tools (Splunk, ELK, App Insights)
• Performance optimization and API rate-handling

Why Join My Client

• Be part of a pioneering fintech/secure banking technology company
• Opportunity to mentor and lead junior developers
• Work in a supportive, collaborative, and technically driven environment
• Gain experience in high-security, mission-critical software projects

Interested? Please Click Apply Now! C# Senior Software Developer