Senior Full Stack Developer

Insight Global; Greater London; Hybrid; GBP 60,000 - 80,000; Full time

Job summary

Insight Global are seeking a Senior Full Stack Developer to join a leading global financial markets organisation, supporting a Frontier AI Cyber Remediation team focused on modernising and enhancing business-critical index management platforms. Three days on-site in London, UK, for a six-month initial contract through March 2027, Inside IR35.

The role covers designing, developing, and enhancing applications across backend services, APIs, databases, and modern UIs.

Qualifications

• Strong hands-on development experience with C# and .NET.
• Frontend development experience with Angular.
• Experience building and supporting APIs and backend services.
• Develop enterprise web apps across frontend and backend.
• Working knowledge of Microsoft SQL Server and T-SQL.
• Investigate and resolve complex app, data, and business issues independently.
• Experience supporting platform migration or modernisation initiatives.
• Experience leveraging AI tools within the software development lifecycle.
• Strong communication, stakeholder management, and problem-solving skills.

Responsibilities

• Design, develop, and enhance applications supporting migration and management of critical financial data platforms.
• Work across backend services, APIs, databases, and modern user interfaces.
• Collaborate with product teams, business stakeholders, and engineers to deliver scalable, secure solutions.
• Play a key role in platform modernisation initiatives and improve performance and quality.

Skills

C#

.NET

Angular

API development

SQL Server

T-SQL

Microservices

RESTful APIs

CI/CD

Terraform

Tools

AWS

Terraform

Job description

Insight Global are seeking a Senior Full Stack Developer to join a leading global financial markets organisation, supporting a Frontier AI Cyber Remediation team focused on modernising and enhancing business-critical index management platforms.

This position requires 3 days onsite in London, UK for a 6-month initial contract through March 2027 and is Inside IR35.

As a Senior Full Stack Developer, you will be responsible for designing, developing, and enhancing applications that support the migration and management of critical financial data platforms. Working across backend services, APIs, databases, and modern user interfaces, you will collaborate closely with product teams, business stakeholders, and engineers to deliver scalable, secure, and reliable solutions. You will also play a key role in platform modernisation initiatives, troubleshooting complex technical issues, and improving application performance and quality.

Must-Have Requirements Include:

• Strong hands-on development experience with C# and .NET
• Experience with frontend development using Angular
• Experience building and supporting APIs and backend services
• Experience developing enterprise web applications across both frontend and backend technologies
• Working knowledge of Microsoft SQL Server and T-SQL
• Ability to investigate and resolve complex application, data, and business issues independently
• Experience supporting platform migration, transformation, or modernisation initiatives
• Experience leveraging AI tools within the software development lifecycle
• Strong communication, stakeholder management, and problem-solving skills

Plusses Include:

• Experience working with AWS or cloud-hosted applications
• Knowledge of AWS services such as EC2 and Lambda
• Experience modernising or migrating legacy .NET applications
• Experience working with microservices architectures and RESTful APIs
• Exposure to CI/CD pipelines and automated deployment processes
• Experience with Infrastructure as Code tools such as Terraform
• Experience working with financial, market, or benchmark data
• Understanding of index calculations, configurations, or lifecycle management
• Experience analysing and reconciling historical datasets
• Experience working within highly secure, business-critical enterprise environments
• Financial Services or Capital Markets industry experience

If you're an experienced Full Stack Developer looking to contribute to large-scale modernisation initiatives within a global financial services environment, we'd love to hear from you.