Software Developer, Web Developer

We're looking to engage an experienced Full Stack Developer to deliver a defined package of security and compliance-focused enhancements to our client's web platform.

This is a short-term, well-scoped contract focused on strengthening authentication, auditing, and application security within an existing production system.

You will be responsible for implementing several targeted improvements to a live ASP.NET MVC application, including:

• Adding multi-factor authentication (MFA) to user login
• Implementing step-up verification for sensitive user actions to confirm user presence at the point of authorisation
• Enhancing audit logging to capture user actions with timestamps
• Reducing security vulnerabilities by updating legacy libraries and resolving App Check warnings
• Producing clear technical documentation and handing over to the internal team

• ASP.NET MVC (.NET Framework 4.8)
• C#
• JavaScript, HTML, CSS
• REST APIs

• Strong background in authentication and authorisation patterns
• Experience securing high-risk or regulated user actions (e.g. approvals, authorisations)
• Comfortable working independently on well-defined enhancements
• Ability to work within an existing codebase and platform constraints
• Clear documentation and handover skills

• Experience in regulated environments
• Familiarity with step-up authentication or electronic signature workflows
• Pragmatic approach to improving security without large-scale rewrites

For more info, contact Ruben Davis at Synergy