Developer C# / .NET as Freelancer (all genders)

Job Description

About Vexcash AG

VEXCASH AG is Germany’s leading online provider of short-term loans. We offer our customers a quick and straightforward solution to bridge the gap until their next payday. More than 800,000 customers already rely on our service. Thanks to our innovative approach, they can secure financial liquidity without having to commit to a long-term agreement.

We are looking for an experienced Developer C# / .NET to join our team and contribute to the development of modern, reliable, and scalable web applications in the FinTech sector as Freelancer.

You will work in a skilled and collaborative environment using modern Microsoft technologies, primarily .NET 8+ and ASP.NET Core. Your main focus will be on designing and developing robust backend services, APIs, and data-driven applications while ensuring high standards of code quality, performance, security, and maintainability.

Your responsibilities

Develop clean, maintainable, testable, and reusable C# code based on business requirements and user stories

Design, develop, and maintain backend applications and services using .NET 8+, ASP.NET Core, and Entity Framework Core

Design and implement RESTful APIs following best practices and scalable architecture principles

Work with SQL Server, including data modelling, query optimization, and performance tuning

Work with Entity Framework Core and ADO.NET for efficient data access and persistence

Implement automated unit and integration tests to ensure software quality and reliability

Apply software architecture principles, design patterns, and clean code practices

Collaborate using Git-based workflows and participate in code reviews

Contribute to CI/CD pipelines and automated deployments

Work with Microsoft Azure services and cloud-based architectures

Analyze, troubleshoot, and resolve technical, functional, and performance issues

Contribute to the continuous improvement of code quality, architecture, scalability, and development processes

What you bring

Strong professional experience with C# and the .NET ecosystem

Hands-on experience with .NET Framework, including maintenance and enhancement of legacy applications

Strong experience with .NET 8+ and ASP.NET Core for modern backend development

Solid experience with Entity Framework Core and ADO.NET

Proven experience designing and building RESTful APIs

Strong knowledge of SQL Server, relational database design, and query optimization

Good understanding of software architecture principles, design patterns, and clean code

Experience with automated testing frameworks such as xUnit, NUnit, or MSTest

Familiarity with CI/CD pipelines and automated deployment processes

Experience with Microsoft Azure and cloud-based application architectures

Experience working in agile development environments

Strong analytical and problem-solving skills with a strong focus on code quality

Good command of English, German is a plus

Remote full-time en 66,000–76,000 GBP/yr

Remote full-time en 10,000–120,000 USD/yr