Regular .NET Developer (Card Payment Systems)

Margo Group

Warsaw Remote contract

Posted: January 23, 2026

Required Skills

Job Description

About the role
We are looking for a Regular .NET Developer to join a team responsible for developing and maintaining core card payment systems - from transaction authorization and settlement to integrations with external payment services.
The systems process hundreds of thousands of transactions daily, so performance, availability and security are key priorities.
Work model: Remote-first with scheduled on-site team meetings (2 days per month in Warsaw).

Responsibilities
- Develop and maintain .NET applications in card payment domain
- Design and implement new functionalities according to business and regulatory requirements
- Integrate systems with external services (REST, SOAP, messaging queues)
- Optimize performance, availability and security of applications
- Cooperate with Analysts, Architects and QA in Agile/Scrum teams
- Participate in SIT/UAT testing, code reviews and preparation of technical documentation

Required skills
- Commercial experience with C# and .NET (Framework / Core)
- Experience with ASP.NET Core, Angular and WebAPI
- Knowledge of Entity Framework, LINQ, Dapper
- Experience with SQL Server (T-SQL) and query optimization
- Knowledge of SOLID principles and design patterns
- Experience writing unit tests (xUnit / NUnit)
- Experience with system integrations (REST, SOAP, JSON, XML)
- Experience working in Agile environment
- Knowledge of Git, CI/CD and TeamCity

Language requirements
- Polish: native or C2 level (required)
- English: professional level enabling work with technical documentation

Nice to have
- Experience in card payments / payment processing domain
- Knowledge of Docker / Kubernetes
- Experience working on high-availability or complex distributed systems

Margo Offers:
- B2B cooperation
- Remote working model
- Benefits such as medical care and sports card
- Co-financing trainings, certification exams and post-graduate studies
- Ability to work in an international consulting company on ambitious projects
- Possibility to get involved in outside-project activities with additional remuneration)
- Excellent working atmosphere, integration events

Why Apply Through MisuJob?

AI-Powered Job Matching: MisuJob uses advanced artificial intelligence to analyze your skills, experience, and career goals. Our matching algorithm compares your profile against thousands of job requirements to find positions where you have the highest chance of success. This saves you hours of manual job searching and ensures you only see relevant opportunities.

One-Click Applications: Once you create your profile, applying to jobs is effortless. Your resume and cover letter are automatically tailored to highlight the most relevant experience for each position. You can apply to multiple jobs in minutes, not hours.

Career Intelligence: Beyond job matching, MisuJob provides valuable career insights. See how your skills compare to market demands, identify skill gaps to address, and understand salary benchmarks for your experience level. Make data-driven decisions about your career path.

Frequently Asked Questions

How do I apply for this position?

Click the "Register to Apply" button above to create a free MisuJob account. Once registered, you can apply with one click and track your application status in your dashboard.

Is MisuJob free for job seekers?

Yes, MisuJob is completely free for job seekers. Create your profile, get matched with jobs, and apply without any cost. We help you find your dream job without any hidden fees.

How does AI matching work?

Our AI analyzes your resume, skills, and experience to understand your professional profile. It then compares this against job requirements using natural language processing to calculate a match percentage. Higher matches mean better fit for the role.

Can I apply to jobs in other countries?

Absolutely. MisuJob features jobs from companies worldwide, including remote positions. Filter by location or look for remote opportunities to find jobs that match your preferences.

Ready to Apply?

Join thousands of job seekers using MisuJob's AI to find and apply to their dream jobs automatically.

Interested in this position?