We are looking for an experienced Lead/Senior .NET Engineer to join a long-term modernization initiative focused on transforming a large-scale enterprise platform from .NET Framework 4.8 to .NET 10. This is a hands-on engineering role where you'll work on modernizing backend architecture, migrating legacy components, improving code quality, and preparing the platform for cloud-native deployment on AWS. You'll collaborate with experienced engineers in an Agile environment while helping shape the future architecture of a mission-critical system.
Responsibilities:
- Drive the migration of a large enterprise application from .NET Framework 4.8 to .NET 10.
- Modernize backend services and replace legacy Windows-specific dependencies with cross-platform solutions.
- Migrate a large Entity Framework 6 data model to EF Core 8, one bounded context at a time.
- Refactor legacy code following modern architecture principles and best engineering practices.
- Improve automated testing by introducing unit test coverage and quality gates.
- Collaborate with DevOps engineers on containerization, Docker configuration, and AWS deployment.
- Participate in architecture discussions, code reviews, technical planning, and Agile ceremonies.
Requirements:
- 5+ years of commercial experience with C#/.NET backend development.
- Strong expertise with ASP.NET, ASP.NET Core, and modern .NET.
- Proven commercial experience migrating applications from .NET Framework to .NET Core / .NET 8+.
- Strong experience with Entity Framework Core.
- Good understanding of DDD, CQRS, and layered architecture.
- Experience building containerized applications using Docker.
- Solid knowledge of xUnit, Moq, and automated testing practices.
- Experience deploying .NET applications to AWS ECS/Fargate and working with ECR.
- Experience with RabbitMQ, MassTransit, or similar messaging technologies.
- Experience with Hangfire or other background job processing frameworks.
- Strong Git workflow and experience working in Agile teams.
Nice to have:
- Experience designing and maintaining CI/CD pipelines.
- Familiarity with Angular applications or micro-frontend architecture.
- Experience implementing automated code coverage in CI.
- Knowledge of performance optimization and scalable distributed systems.
We offer*:
- Flexible working format - remote, office-based or flexible
- A competitive salary and good compensation package
- Personalized career growth
- Professional development tools (mentorship program, tech talks and trainings, centers of excellence, and more)
- Active tech communities with regular knowledge sharing
- Education reimbursement
- Memorable anniversary presents
- Corporate events and team buildings
- Other location-specific benefits
*not applicable for freelancers
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Key team members
Tom Fowler
Meridith Cass
Olivia Crozier
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