We are searching for a Senior .NET Engineer to become part of the migration team, contributing to the breakdown of a .NET Framework 4.8 / VB.NET desktop application into ASP.NET Core (Current) backend services running on Kubernetes. The engagement kicks off with the project's highest-risk element — profiling and replacing a 14,518-line VB.NET data layer with EF Core repositories against a multi-tenant PostgreSQL schema secured by Row-Level Security — and then extends across backend services depending on team allocation.

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

Responsibilities

- Support the breakdown of a legacy desktop application into modern backend services
- Architect and build backend components that align with the target architecture and established design patterns
- Team up with colleagues to shape scalable data access strategies for multi-tenant use cases
- Take part in code reviews and share technical insights to elevate overall code quality
- Examine legacy business logic to guarantee functional parity across newly delivered services
- Join architectural conversations and help sharpen technical direction across workstreams
- Diagnose and resolve issues that surface throughout the migration lifecycle
- Assist with deployment activities and help keep services running reliably in containerised environments

Requirements

- No less than 3 years of hands-on professional experience in backend .NET engineering within production systems
- Practical delivery of REST APIs consumed by a real frontend inside a team setting
- Exposure to containerised deployments, including having released services running on Docker
- Assured,



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

Nice to have

- Background with PostgreSQL, including schema design, indexing, and multi-tenant data patterns
- Awareness of Helm for handling Kubernetes application deployments
- Working understanding of Kubernetes for container orchestration and service operations
- Applied familiarity with OAuth2 for securing modern web applications and APIs
- Prior exposure to Visual Basic .NET for reading or maintaining legacy components
- Familiarity with 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