Senior .NET Engineer: Modernize a Critical Payment Platform

Reply; Katowice; Hybrid; PLN 179,000 - 246,000; Full time

Benefits offered by this job

Motivizer Benefits Platform (PLN 550/月

Language Courses

Internal community & events

Regular training opportunities

Job summary

Nexi Digital is seeking a Senior Software Engineer to drive the modernization of a payment platform by migrating a large ASP.NET WebForms/MVC monolith from .NET Framework 4.x to .NET 8, including database and system integrations in an on-premise setup.

You will leverage AI-assisted development tools, refactor for SOLID and clean architecture, and build automated tests to verify migration steps, while mentoring teammates and collaborating with stakeholders.

Qualifications

• University degree in computer science or a comparable field of study.
• 6+ years of commercial software development experience.
• Experience with C# and .NET across generations (ASP.NET WebForms/MVC and ASP.NET Core).
• Experience migrating legacy applications (re-platforming, incremental refactoring).
• Strong knowledge of SOLID and clean architecture.
• Experience with SQL Server and data-layer refactoring.
• Experience with AI-assisted development tools on daily workflow.
• Fluency in Polish and very good English communication.
• Hybrid work availability; monthly office visits.

Responsibilities

• Analyze legacy codebase and plan incremental migration paths.
• Migrate components from .NET Framework to .NET 8 / ASP.NET Core.
• Refactor towards SOLID and clean architecture during migration.
• Modernize SQL Server data layer and integrations.
• Leverage AI tools to accelerate analysis, refactoring, and testing.
• Build automated unit and integration tests for migration verification.
• Collaborate with teams and stakeholders on scope and sequencing.
• Mentor junior developers and share modernization know-how.

Skills

C#

.NET

ASP.NET WebForms

SQL Server

AI-assisted development

Unit testing

Polish

English

Education

CS degree or equivalent

Tools

GitHub Copilot

LLM tools

Job description

Nexi Digital is seeking a Senior Software Engineer to drive the modernization of a payment platform by migrating a large ASP.NET WebForms/MVC monolith from .NET Framework 4.x to .NET 8, including database and system integrations in an on-premise setup.

You will leverage AI-assisted development tools, refactor for SOLID and clean architecture, and build automated tests to verify migration steps, while mentoring teammates and collaborating with stakeholders.