Senior Full-Stack Developer, React, .NET

This is a fully remote position, open to applicants in Poland.

📋 Description

• Design, develop, and deploy production-level C#/.NET services and REST APIs that handle high-volume payment and risk data while adhering to PCI DSS standards.

• Take ownership of typed OpenAPI contracts with the front end, ensuring proper versioning and compatibility with previous iterations.

• Write optimized data access solutions for the operational database and Microsoft Fabric Gold-layer risk tables, catering to analyst-scale data volumes.

• Implement security measures such as authentication, authorization, audit logging, and PCI-compliant handling of tokenized card information.

• Contribute to the React and TypeScript front end by developing features end to end, as well as engaging in code reviews and collaborative sessions.

• Utilize Claude Code or similar agentic coding tools as the main coding accelerator, complemented by unit, integration, and contract testing.

• Maintain Dockerfiles and Docker Compose configurations.

• Assist in deployments to AKS and contribute to Azure DevOps CI/CD processes.

• Execute tasks according to the architecture guidelines provided by the client’s architecture group.

• Proactively identify risks and transfer responsibilities to the internal team for ownership.

• Join a cutting-edge risk analysis and scoring platform for a payments technology firm, merging client risk rules with AI-enhanced pre-scored risk feeds over high-volume payment data while complying with PCI DSS.

⛳️ Requirements

• Over 7 years of experience in commercial software development.

• More than 5 years of experience in production-grade C#/.NET, including ASP.NET Core, asynchronous programming, dependency injection, and EF Core or Dapper.

• Strong skills in API design, including REST conventions, OpenAPI contracts, versioning, and evolving APIs without impacting consumers.

• Proficient in relational databases and distributed systems, including schema design, query optimization, transactional integrity, idempotency, and error handling.

• Working knowledge of React and TypeScript; capable of building features from start to finish and reviewing front-end code.

• Daily hands-on experience with agentic AI coding tools like Claude Code, Cursor, Copilot Workspace, Codex, or similar.

• Proven history of delivering AI-accelerated code that performs well in production, along with the ability to demonstrate the workflow live.

• Experience with Docker, including multi-stage builds and security hardening.

• Familiarity with Docker Compose and Kubernetes, preferably AKS.

• Experience with testing frameworks such as xUnit or NUnit, integration testing with real dependencies like Testcontainers, and contract testing.

• Proficient in Git and CI/CD practices, including Azure DevOps, GitHub Actions, or similar platforms.

• Ability to work autonomously within an existing codebase.

• Additional desirable skills: experience in payments, card processing, risk/fraud, merchant services, PCI-compliant systems, Microsoft Fabric, Delta Lake, analytical data stores, Azure Service Bus, Event Hubs, Kafka, OpenTelemetry, Application Insights, OAuth2/OIDC, Microsoft Entra ID, managed identity, Python, LLM-integrated or agentic applications such as LangGraph, and prior consulting experience.

🏝️ Benefits

• Flexible and remote work options.

• Opportunities to work on international projects with top global clients.

• Travel opportunities related to international projects.

• A non-corporate working environment.

• Access* to language classes.

• Access* to knowledge-sharing initiatives.

• Access* to private healthcare and life insurance.

• Access* to a multisport card.

• Availability and conditions of individual benefits may vary based on the chosen form of cooperation.