Remote Senior .NET Fullstack Engineer

Optiveum; Warszawa; Remote; PLN 181,000 - 217,000; Full time

Job summary

Optiveum is seeking a Senior .NET Fullstack Developer to join our client team in a 100% remote role. You will work on business-critical full-stack apps, modernizing legacy systems, and building scalable APIs in .NET and Azure.

The role emphasizes ownership, CI/CD with GitHub Actions, strong testing practices, documentation, and collaboration with cross-functional teams. Fluent English is required; Polish-based remote work is supported.

Qualifications

• Senior-level experience in full-stack software development.
• Strong C# and .NET skills for legacy modernization.
• Experience with Azure cloud services and GitHub Actions.
• Knowledge of APIs, architecture, and security best practices.
• Fluent English communication.

Responsibilities

• Develop, maintain, and improve full-stack applications.
• Migrate legacy solutions to current .NET versions.
• Work across UI, backend, APIs, and data sources.
• Design features for research-related entities.
• Establish and improve Azure infrastructure.
• Create and maintain CI/CD pipelines with GitHub Actions.
• Enhance quality via automated tests, reviews, observability, and docs.
• Support applications through lifecycle balancing maintenance and new development.

Skills

Senior-level experience

C# & .NET

Azure

CI/CD (GitHub Actions)

APIs & Architecture

Testing & Observability

Documentation

English fluent

Tools

GitHub Actions

Azure

Job description

Optiveum is seeking a Senior .NET Fullstack Developer to join our client team in a 100% remote role. You will work on business-critical full-stack apps, modernizing legacy systems, and building scalable APIs in .NET and Azure.

The role emphasizes ownership, CI/CD with GitHub Actions, strong testing practices, documentation, and collaboration with cross-functional teams. Fluent English is required; Polish-based remote work is supported.