Senior Software Engineer - Identity & Authentication

Project Contractor

About the Role
In the European Client Identity team, we are building and operating Vanguard's authentication
and MFA platform used by hundreds of thousands of clients across the UK and Europe.
This is a hands-on senior full-stack role focused on designing, building, deploying, and
operating cloud-based identity services. You will contribute across backend APIs, cloud
infrastructure, and frontend experiences - with React as the preferred frontend framework
for new UI work. You will work in a highly regulated environment where security, reliability, and
operational discipline matter.
You don't need to be an identity expert on day one - but you do need strong full-stack
fundamentals, cloud experience, and a responsible, methodical engineering mindset.

What You'll Do
• Build and evolve backend services that support login, MFA, and client authentication
• Design and implement REST APIs using NestJS / TypeScript
• Build frontend experiences using React where new UI development is required
• Integrate with identity and MFA platforms (e.g. Transmit Security, Auth0)
• Deploy and operate services on AWS, using Infrastructure as Code
• Run and maintain services in production, including:
○ Database migrations and updates
○ Manage vendor-specific software services running in AWS
• Write automated tests and contribute to improving test coverage and quality
• Participate in CI/CD pipelines, deployments, and operational procedures
• Work closely with product and security stakeholders to translate requirements into
technical solutions
• Continuously improve engineering standards, tooling, and reliability

What We're Looking For (Must-Have)
• Strong backend engineering fundamentals with Node.js and NestJS or Express
• TypeScript across frontend and backend
• Experience designing and building REST APIs
• Understanding of authentication protocols: OAuth 2.0, JWT, MFA flows
• Hands-on experience with AWS (ECS, Lambda, CloudFront, S3, Secrets Manager)
• Familiarity with Infrastructure as Code (CloudFormation or Terraform)
• Experience with containerised workloads (Docker)
• Strong Git practices and CI/CD experience (GitHub Actions or similar)
• Experience writing unit and integration tests (Jest)

Nice to Have
• React experience for frontend development - preferred for any new UI work
• Experience with identity, authentication, or MFA systems
• Familiarity with Kong API Gateway or similar
• Exposure to Aurora PostgreSQL or DynamoDB
• Knowledge of microservices architectures
• Exposure to security concepts (IAM, encryption, networking)
• Experience with observability tooling (OpenTelemetry, Honeycomb, Grafana)
• Experience in regulated or enterprise environments

Our Tech Stack
AWS • TypeScript • React • Node.js (NestJS) • REST APIs • Auth0 • Transmit Security •
Kong Gateway • GitHub • GitHub Actions • CloudFormation

How We Work

Vanguard has implemented a hybrid working model for the majority of our crew members, designed to capture the benefits of enhanced flexibility while enabling in-person learning, collaboration, and connection. We believe our mission-driven and highly collaborative culture is a critical enabler to support long-term client outcomes and enrich the employee experience.