Senior .NET Software Engineer - 6 months - London - £500/day - Inside IR35

Senior .NET Software Engineer - 6 months - London - £500/day - Inside IR35

We are seeking an experienced Senior .NET Software Engineer to join a global technology services organisation on a 6-month hybrid contract based in London City . The successful candidate will contribute to and lead the development of high-quality, data-intensive applications for a major financial markets client, combining strong Back End engineering with cloud and UI expertise in a fast-paced, agile environment.

Key Responsibilities:

• Lead and contribute to software design and architecture, producing clean, efficient, and scalable code across the full development lifecycle
• Design and implement RESTful APIs and microservices using C# .NET, ensuring high performance, scalability, and security in production environments
• Develop and maintain UI components for business-critical applications using Angular, JavaScript, and HTML/CSS
• Advocate for and implement engineering best practices including CI/CD, code reviews, automation, and performance tuning
• Ensure high quality and reliable products through unit, integration, and BDD test suites using frameworks such as MSTest, tSQLt, Cucumber, and Mocha
• Write and optimise complex SQL Server stored procedures and T-SQL for large-scale, data-intensive applications
• Collaborate closely with business and engineering partners to deliver products and solutions aligned to customer needs and business goals
• Drive a culture of engineering excellence through mentorship, peer reviews, and promoting standard methodologies across the team
• Continuously optimise systems for performance, scalability, and security

What You Will Ideally Bring:

• 8+ years of experience as a Software Developer, architecting and developing large-scale data-intensive applications in an enterprise environment
• Strong proficiency in C# .NET, RESTful API design, and microservices architecture
• Solid experience in database modelling, design, performance tuning, and optimisation using SQL Server and T-SQL stored procedures
• Hands-on UI development experience using Angular, JavaScript, and HTML/CSS
• Strong understanding of AWS cloud infrastructure and native services including EC2, EKS, Lambda, SQS, SNS, and AWS Glue
• Experience working in agile environments with a focus on CI/CD, collaboration, and continuous improvement
• Experience in Financial Markets, particularly Equities and/or Fixed Income
• Familiarity with Sybase and PostgreSQL database management and optimisation
• Desirable: prior experience with Java (including SpringBoot) and/or Python for cross-platform integrations, and experience across Business Analysis, QA, or Delivery Management

Contract Details:

• Duration: 6 months
• Rate: £500/day (Inside IR35)
• Location: London City (Hybrid - 3 days on-site)
• Start Date: ASAP

• 8+ years of experience as a Software Developer, architecting and developing large-scale data-intensive applications in an enterprise environment
• Strong proficiency in C# .NET, RESTful API design, and microservices architecture
• Solid experience in database modelling, design, performance tuning, and optimisation using SQL Server and T-SQL stored procedures
• Hands-on UI development experience using Angular, JavaScript, and HTML/CSS
• Strong understanding of AWS cloud infrastructure and native services including EC2, EKS, Lambda, SQS, SNS, and AWS Glue
• Experience working in agile environments with a focus on CI/CD, collaboration, and continuous improvement
• Experience in Financial Markets, particularly Equities and/or Fixed Income
• Familiarity with Sybase and PostgreSQL database management and optimisation
• Desirable: prior experience with Java (including SpringBoot) and/or Python for cross-platform integrations, and experience across Business Analysis, QA, or Delivery Management