Senior Software Engineer - React.js,.Net, AWS

Landauer, one of the flagship brands within Fluke Health Solutions, is the world leader in personal radiation monitoring services, having protected radiation workers for over 60 years across hospitals, nuclear facilities, industrial organisations, and research institutions worldwide. Landauer's expertise spans the full spectrum of occupational dosimetry — from the physical science of radiation measurement to the regulatory frameworks that govern worker protection.

myLDR is Landauer's next-generation cloud-based, self-service radiation safety and dosimetry management platform — bringing the complete dosimetry program lifecycle into a modern, cloud-native portal that puts operational control directly in the hands of Radiation Safety Officers, department administrators, and individual workers.

Full-Stack Software Engineer About the Role

We are hiring a Full-Stack Software Engineer with strong cloud-native and serverless experience. You will design and ship features across a .NET backend, AWS infrastructure, and a React TypeScript frontend — working with high standards for code quality, test coverage, and security.

Required Skills

Backend

• C# on .NET 8 / .NET 10
• SQL Server, OpenSearch backend
• Valkey caching
   

Frontend

• React 19
   

AWS Cloud Services

• AWS Lambda + API Gateway — serverless-first, cold-start aware
• Amazon Cognito — OAuth 2.0 client credentials and JWT validation
• AWS SSM Parameter Store — secrets and configuration management (no hardcoded credentials)
• Amazon S3 — object storage

• Amazon SQS / SNS — async messaging and event-driven processing

   

• AWS SAM / CloudFormation — infrastructure as code
• AWS IAM — least-privilege roles and policies, VPC security groups
• Amazon CloudWatch + X-Ray — structured logging, distributed tracing, alerting
   

Observability

• Datadog — RUM, APM, log correlation, error tracking, dashboards

CI/CD

• GitHub Actions — automated build, test, lint, and deploy pipelines

  
   

Good to Have

• Experience with Spec-Driven Development (SDD) — writing feature specs before implementation, using specs as the contract for planning, task breakdown, and acceptance criteria
• Comfortable using AI coding agents (GitHub Copilot Agent, custom agents) as part of day-to-day development — prompting, reviewing, and validating agent-generated code

• Familiarity with agent-assisted workflows via UI — slash-command agents, skill-based automation, and agentic planning tools integrated into the IDE

   

What you'll Gain joining our Team

• This is more than a software engineering role — it is an opportunity to grow meaningfully as an engineer, a technical contributor, and a professional in a domain where the work genuinely matters.

   

Deep Technical Growth

• Master serverless-first distributed systems in a production environment where correctness constraints push you to truly understand the patterns — idempotency, eventual consistency, saga orchestration, and event-driven design are not buzzwords here, they are daily engineering decisions with real consequences
• Sharpen your system design craft by owning features end-to-end — from data model to deployed infrastructure — in a team culture that treats design as a first-class activity and gives you the space to think before you build

• Work across the full stack — backend Lambda services in .NET C# 8/10, frontend dashboards in React 19 with a mature UI design system, data engineering in SQL Server on RDS, and infrastructure as code in AWS CDK — broadening or deepening your skills depending on where you start

   

   

Architectural Ownership

• You will not be handed tickets and told to implement — you will be expected to shape how features are built, contribute meaningfully to architectural decisions, and leave the codebase and system design better than you found it
• Your architectural contributions and technical specifications will become the reference point for how the platform evolves — giving you visible, lasting technical influence on a system used by hundreds of thousands of workers

Domain that matters

• Work on software that has direct real-world health and safety consequences — the kind of mission that makes engineering feel purposeful, not transactional
• Develop rare domain expertise at the intersection of radiation safety regulation, occupational health compliance, and enterprise SaaS — a combination that is genuinely valuable and not easily replicated elsewhere
• Collaborate with Radiation Safety Officers, Health Physicists, and regulatory compliance experts — expanding your professional perspective well beyond a typical software engineering team

Team & Culture

• Join a team that takes engineering craft seriously — design reviews, blameless post-mortems, and allocated time for technical debt are not aspirations, they are how the team operates
• Work in an environment where your opinion on architecture matters — senior engineers here are heard, not managed