Senior .NET Developer

GFT Technologies; Poznań; Hybrid; PLN 260,000 - 380,000; Full time

Benefits offered by this job

Hybrid work

Benefit package

Online training and certifications

Work From Anywhere

Job summary

GFT Poland is seeking an experienced backend developer to design, implement, and maintain scalable .NET/C# services in modern distributed environments. You will work in Agile teams, taking ownership from analysis to deployment and operational support, collaborating with architects, DevOps, and QA to ensure high-quality systems.

The role requires strong knowledge of REST APIs, ASP.NET Core, and distributed architectures, with a focus on reliability, performance, and best practices in engineering.

Qualifications

• Over 5 years of commercial experience with .NET and C#.
• Solid knowledge of OOP, SOLID principles and clean code.
• Experience building RESTful APIs and distributed systems.
• Experience with ASP.NET Core and asynchronous programming.
• Knowledge of relational databases and Entity Framework Core.
• Strong command of English.

Responsibilities

• Design and implement backend services and REST APIs using .NET/C#.
• Develop production-ready solutions in distributed and cloud-native architectures.
• Plan and execute development tasks independently.
• Contribute to technical design and architecture discussions.
• Write and maintain technical documentation and design notes.
• Perform code reviews and ensure adherence to engineering standards.
• Build and maintain automated tests (unit, integration, API).
• Troubleshoot and resolve application and integration issues.
• Support CI/CD pipelines and deployment processes.
• Implement monitoring, logging and observability practices.
• Work with asynchronous processing and messaging systems.
• Share knowledge and support junior engineers.
• Experience working in Agile/Scrum teams.

Skills

NET/C#

REST APIs

ASP.NET Core

OOP

SOLID principles

Agile/Scrum

English

Tools

RabbitMQ

Kafka

Azure Service Bus

Docker

Kubernetes

Entity Framework Core

xUnit

NUnit

FluentAssertions

Git

Job description

We are GFT Poland. WE KNOW how to tackle complex issues with innovative approach to deliver the highest value. Our reputation has been built around one simple rule: we do not overpromise, WE DELIVER. We deliver to our employees, clients and partners. WE GROW as you grow, so investing in you is our business strategy. Caring for each other is our priority. WE CARE who you are, what you need, how you feel. WE CARE to smile, have fun and develop as human beings.

Why Choose GFT?

• A culture of top performance
• Deep tech IT engineering & consulting
• 1,200 skilled & top-class experts
• 77% of the team are regular/senior
• Great Place To Work
• Products that contribute to a sustainable world
• Competitive salary and benefits
• Ambitious projects, trainings and tools you need to flourish
• Google Cloud Partner of the Year - for going above and beyond for customers

What will you do?

You will design, develop and maintain scalable backend services in modern distributed environments using .NET and C#. Working in Agile teams, you will take ownership of end-to-end delivery – from technical analysis and implementation to deployment and operational support. You will collaborate closely with architects, DevOps and QA to ensure high-quality, secure and reliable systems while actively contributing to improving engineering standards, software quality and delivery processes.

• Design and implement backend services and REST APIs using .NET/C#
• Develop production-ready solutions in distributed and cloud-native architectures
• Plan and execute development tasks independently
• Contribute to technical design and architecture discussions
• Write and maintain technical documentation and design notes
• Perform code reviews and ensure adherence to engineering standards
• Build and maintain automated tests (unit, integration, API)
• Troubleshoot and resolve application and integration issues
• Support CI/CD pipelines and deployment processes
• Implement monitoring, logging and observability practices
• Work with asynchronous processing and messaging systems
• Share knowledge and support junior engineers
• Min. 5 years of commercial experience with .NET and C#
• Strong knowledge of OOP, SOLID principles and clean code
• Experience with ASP.NET Core
• Practical knowledge of asynchronous and multithreaded programming
• Experience building RESTful APIs and distributed systems
• Knowledge of event-driven architecture and messaging tools (e.g. RabbitMQ, Kafka, Azure Service Bus)
• Experience with dependency injection and backend frameworks
• Experience with CI/CD pipelines and Git-based workflows
• Experience with automated testing frameworks (xUnit, NUnit, FluentAssertions)
• Understanding of testing strategies (unit, integration, contract tests)
• Knowledge of relational databases and Entity Framework Core
• Ability to write efficient SQL queries and debug data issues
• Familiarity with logging and monitoring tools
• Strong problem-solving skills and ability to work independently
• Experience working in Agile/Scrum teams
• Good command of English

Nice to have

• Experience with Azure or AWS
• Knowledge of Docker and Kubernetes
• Experience with microservices architecture
• Basic frontend knowledge (Angular, React, TypeScript)
• Familiarity with gRPC
• Experience in performance optimization and resiliency patterns
• Practical use of AI coding assistants (e.g. Copilot, ChatGPT)
• Knowledge of Spec-Driven Development

We offer

• Hybrid work in one of our locations: Lodz, Poznan, Krakow, Warszawa, Wroclaw (2 office days per week)
• Working in a highly experienced and dedicated team
• Benefit package tailored to your needs (medical, sport, lunch subsidy, life insurance, etc.)
• Online training and certifications
• Work From Anywhere (up to 140 days/year abroad)