.NET Backend Developer

On behalf of our Client, a well-established financial institution from the Caribbean region Mobilunity is looking for a .NET Backend Developer for a long-term engagement.

Our Client is the largest bank in the Caribbean region that serves 14 countries/territories. The aim is to make this organization from a traditional bank into a new era of fintech, working on the edge of what current fintech may offer.

Responsibilities:

• Design, develop, and maintain scalable backend microservices for Instant Payment System (IPS) components.
• Implement and support ISO 20022 financial messaging (pacs.008, pacs.002, camt.056, etc.).
• Develop RESTful APIs for integrations with front-end and external banking systems.
• Work closely with the API Gateway, Core Banking, and Fraud/AML services.
• Ensure security, data integrity, and reliability across distributed services.
• Participate in country-specific configurations (BIC, currency, limits, URLs).
• Write unit and integration tests, perform debugging, and maintain CI/CD pipelines.
• Collaborate with architects, leads, and regional IT teams to ensure solution consistency and code reusability.

Requirements:

• 3+ years of experience in backend development using .NET / .NET Core
• Strong understanding of REST API design and microservice architecture.
• Experience with message-based or event-driven systems (e.g., RabbitMQ, Kafka, or Azure Service Bus).
• Proficiency in working with SQL and/or NoSQL databases (SQL Server, PostgreSQL, DynamoDB, etc.).
• Familiarity with secure API communication (TLS 1.2+, certificates, signatures).
• Experience with containerization (Docker, Kubernetes) and CI/CD pipelines (GitHub Actions, Azure DevOps, Jenkins).
• Understanding of financial integrations or ISO 20022 standards will be a big plus.
• Good command of English (Upper-Intermediate or higher) for daily communication with the client and technical teams.

Nice to Have:

• Experience with AWS (S3, Parameter Store, ECS, EKS, Secrets Manager).
• Familiarity with Vault, SIEM, or audit logging solutions.
• Background in FinTech, banking, or payment systems.
• Knowledge of Domain-Driven Design (DDD) or Clean Architecture principles.

In return we offer:

• The friendliest community of like-minded IT-people
• Open knowledge-sharing environment – exclusive access to a rich pool of colleagues willing to share their endless insights into the broadest variety of modern technologies
• Mobilunity Medical Insurance program designed to attend our teams’ needs
• Paid vacations and sick leaves, including 5 paid days per year that don’t require a sick note
• Perfect office location in the city-center (900m from Lukyanivska metro station with a green and spacious neighborhood) or remote mode engagement: you can choose a convenient one for you, with a possibility to fit together both
• No open-spaces setup – separate rooms for every team’s comfort and multiple lounge and gaming zones
• English classes in 1-to-1 & group modes with elements of gamification
• Neverending fun: sports events, tournaments, music band, multiple affinity groups

Come on board, and let’s grow together!