A large-scale industrial software platform is undergoing a backend modernization. The current system is built on a legacy application framework that is being phased out, and the goal is to transition to standard modern .NET components. The role focuses on working with an existing, complex codebase and contributing to a gradual, controlled migration.

Responsibilities

• Participate in the migration from a legacy .NET framework to modern .NET architecture

• Maintain and improve an existing production system

• Design and implement performant backend solutions

• Work with database performance optimization and troubleshooting

• Collaborate with frontend developers on API contracts

Mandatory Technical Skills

• Strong experience with C# and modern .NET

• Solid understanding of collections and data structures

• Experience with asynchrony and parallelism

• Strong LINQ skills

• Extensive ASP.NET experience

• Hands-on experience with EF Core (migrations, transactions, performance tuning)

• Strong debugging skills, especially in large legacy codebases

• Experience with Microsoft SQL Server (performance tuning, troubleshooting)

• Experience working with CI/CD pipelines (e.g., Azure DevOps)

• Good theoretical understanding of algorithms, including:

  • Time and space complexity

  • Designing efficient solutions

Nice-to-Have Skills

• Experience migrating away from legacy .NET frameworks (e.g., ASP.NET Boilerplate / ABP)

• Basic understanding of Vue.js and TypeScript

• Experience working with OpenAPI or similar API contract tools

Practical Details

• Location: Vantaa, Finland

• Onsite requirement: Minimum 4 days/week (work involves physical hardware)

• Start date: April 2026

• Duration: Initial contract until end of 2026, with possible extension into 2027

• Workload: Full-time

• Language: English

• Equipment: Provided by the client