Senior .NET Developer (2205)

Senior .NET Developer

Location: Kraków (Hybrid: 2 days/week) or Remote (Poland-based)

English Requirement: B2+ (majority of team based in the UK)

Business Unit: ClearAccept, part of ClearCourse

We’re looking for a Senior .NET Developer to join our team at ClearAccept, a growing part of the ClearCourse Group. You’ll play a leading role in the design and development of a modern, cloud-native fintech platform used by merchants across the UK.

This is a hands-on engineering position, with added responsibilities in architectural decision-making, mentoring developers, and setting high standards for quality and performance.

What You’ll Be Doing

• Designing and delivering new features for our cloud-based payments platform

• Collaborating with architects, product owners, and engineers to deliver scalable solutions

• Leading by example in applying clean architecture principles and modern coding practices

• Reviewing code, mentoring junior and mid-level developers, and supporting a culture of knowledge sharing

• Contributing to key architectural and technical design decisions

• Applying practices such as TDD/BDD, DDD, and event-driven design to build robust, maintainable systems

• Supporting agile delivery by estimating user stories and actively improving development processes

Key Technologies

• Languages: C#, .NET (latest LTS), TypeScript

• Databases: PostgreSQL (AWS Aurora), DynamoDB, DocumentDB, Redis (ElastiCache)

• Messaging & Architecture: MassTransit (RabbitMQ, Azure Service Bus), MediatR (CQRS), Event-Driven Architecture

• Cloud & DevOps: AWS (Lambda, Cognito, API Gateway, Fargate, SQS, SNS, etc.), Docker, LocalStack

• Practices: TDD/BDD, Domain-Driven Design, Secure Coding (OWASP), CI/CD pipelines

What We're Looking For

• 5+ years of experience in a software development role, with a focus on backend systems

• Deep expertise in C# and .NET for building scalable APIs and services

• Strong experience with asynchronous and multi-threaded programming

• Solid understanding of design patterns and clean architecture principles

• Experience with distributed messaging and event-driven systems

• Background in leading code reviews, mentoring developers, and maintaining code quality

• Strong SQL and NoSQL database knowledge

• Awareness of security best practices and experience writing secure, production-ready code

• Comfortable working in an agile team and contributing to continuous improvement

What We Offer

• Access to MyBenefit Cafeteria platform

• Private healthcare package

• Extra day off for your birthday

• Weekly Pizza Tuesdays

• Relaxation zone with PlayStation and foosball table

• Regular team integration events

• Informal, no dress code environment

• Part of a fast-growing technology group with opportunities for career progression

This is your chance to take the next step in your career, shape the future of payment technology, and work with a supportive, forward-thinking team.

Interested? Apply today and join ClearCourse.