We are looking for a Senior .NET Engineer to join the migration team, working on the decomposition of a .NET Framework 4.8 / VB.NET desktop application into ASP.NET Core (Current) backend services on Kubernetes. The engagement starts with the highest-risk item in the project — characterising and replacing a 14,518-line VB.NET data layer with EF Core repositories against a multi-tenant PostgreSQL schema with Row-Level Security — then continues across backend services depending on team allocation.

All services follow the same patterns throughout: ASP.NET Core, EF Core, PostgreSQL, JWT tenant middleware, Docker, Kubernetes manifests.

Responsibilities

- Contribute to the decomposition of a legacy desktop application into modern backend services
- Design and implement backend components aligned with the target architecture and established patterns
- Collaborate with team members to define scalable data access approaches for multi-tenant scenarios
- Participate in code reviews and share technical insights to raise overall code quality
- Analyze legacy business logic to ensure functional parity across newly built services
- Take part in architectural discussions and help refine technical direction across workstreams
- Investigate and resolve issues encountered throughout the migration lifecycle
- Support deployment activities and help ensure services run reliably in containerised environments

Requirements

- At least 3 years of professional relevant experience in backend .NET engineering on production systems
- Hands-on delivery of REST APIs consumed by a real frontend within a team environment
- Familiarity with containerised deployments, including shipping services running in Docker
- Confident,



production-level command of C# and ASP.NET Core (Current)
- Practical experience with Entity Framework Core, including migrations, global query filters, and optimistic concurrency
- Applied knowledge of OAuth 2.0 and OIDC server-side flows using Microsoft.Identity.Web, along with JWT validation and tenant middleware
- Experience with Docker covering multi-stage builds, secrets handling, and CI image gates
- Hands-on background with xUnit and Testcontainers, with the ability to write meaningful integration tests against a real database
- Strong VB.NET reading comprehension, with the ability to follow and reason about legacy VB.NET code without needing to write it
- Confident English communication at B2 level or higher, in both written and spoken forms

Nice to have

- Experience with PostgreSQL covering schema design, indexing, and multi-tenant data patterns
- Familiarity with Helm for managing Kubernetes application deployments
- Working knowledge of Kubernetes for container orchestration and service operations
- Applied understanding of OAuth2 for securing modern web applications and APIs
- Exposure to Visual Basic .NET for interpreting or maintaining legacy components
- Awareness of XBRL for structured business reporting scenarios

We offer

- International projects with top brands
- Work with global teams of highly skilled, diverse peers
- Healthcare benefits
- Employee financial programs
- Paid time off and sick leave
- Upskilling, reskilling and certification courses
- Unlimited access to the LinkedIn Learning library and 22,000+ courses
- General career opportunities
- Volunteer and community involvement opportunities
- EPAM Employee Groups
- Award-winning culture recognized by Glassdoor, Newsweek and LinkedIn

📌 Senior .NET Engineer (Argentina)
🏢 EPAM Systems
📍 Argentina