Posted 8 h ago
[WAP] Senior Full-Stack Developer (React, .NET)
·Warsaw, Masovian Voivodeship, Poland·via SmartRecruiters
Posted by Software Mind on 4 November 2026. Still on their SmartRecruiters board when we checked 7 min ago. Half of Software Mind's roles come down within 12 days.
remotesenior7+ yrsFull time
What the posting is about
Design, build, and maintain C#/.NET services and REST APIs for a high-volume payment and risk data platform. Collaborate with a frontend-leaning developer in a small AI-first delivery team. Contribute to the React and TypeScript frontend, and use AI coding tools to accelerate development. Maintain Dockerfiles, Compose configurations, and support deployments to AKS. Implement against the target architecture set by the client's architecture group.
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Read out of the posting
Levelsenior
Experience asked7+ years
EmploymentFull time
LocationWarsaw, Masovian Voivodeship, Poland
RemoteYes
Visa sponsorshipNot stated
SalaryNot published, and most postings do not
Posted2026-11-04
Found viasmartrecruiters, direct from their system
We had it within the hour it went up.
The posting, as the company wrote it
Employment: Full-time
Experience level: Mid-Senior Level
Job Description
 
Project – the aim you’ll have
Join a next-generation risk analysis and scoring platform built for a payments technology company. The platform combines the client’s own risk rules with AI-driven, pre-scored risk feeds from a global card network over high-volume payment data under PCI DSS. You’ll own the C#/.NET services and API contracts the analyst-facing apps run on, in a small AI-first delivery team alongside a frontend-leaning developer.
Role – how you’ll contribute
Design, build and ship production C#/.NET services and REST APIs serving high-volume payment and risk data under PCI DSS constraints
Own API contracts with the front end: typed OpenAPI contracts, versioning and backward-compatible change
Write efficient data access against the operational database and Microsoft Fabric Gold-layer risk tables at analyst-scale volumes
Implement security-critical concerns: authentication, authorization, audit logging and PCI-safe handling of tokenized card data
Contribute to the React and TypeScript front end – building features end to end, reviewing and pairing
Use Claude Code or an equivalent agentic coding tool as your primary accelerator, backed by unit, integration and contract tests, while owning the quality of every line merged
Maintain Dockerfiles and Compose configurations, support deployments to AKS and contribute to Azure DevOps CI/CD
Implement against the target architecture set by the client’s architecture group, raise risks early and hand off work the internal team can own
Qualifications
 
 
Expectations – the experience you need
7+ years of commercial software development, including 5+ years of production-grade C#/.NET (ASP.NET Core, async, DI, EF Core or Dapper)
Strong API design: REST conventions, OpenAPI contracts, versioning and evolving APIs without breaking consumers
Relational database and distributed-systems skills: schema design, query tuning, transactional correctness, idempotency, failure handling
Working proficiency in React and TypeScript – able to build features end to end and review frontend code
Daily, hands-on use of agentic AI coding tools (Claude Code, Cursor, Copilot Workspace, Codex or similar) and a track record of shipping AI-accelerated code that holds up in production – you’ll demo your workflow live
Containers: Docker (multi-stage builds, hardening), Docker Compose and Kubernetes (AKS preferred)
Testing discipline: xUnit or NUnit, integration testing with real dependencies (e.g. Testcontainers) and contract testing
Git, CI/CD (Azure DevOps, GitHub Actions or similar) and autonomy in an existing codebase
Additional skills – the edge you have
Payments, card processing, risk/fraud or merchant services experience, ideally with PCI-scoped systems
Microsoft Fabric, Delta Lake or building APIs over analytical data stores
Messaging and observability: Azure Service Bus, Event Hubs or Kafka; OpenTelemetry and Application Insights
Identity standards: OAuth2/OIDC, Microsoft Entra ID, managed identity
Python and exposure to LLM-integrated or agentic applications (e.g. LangGraph); prior consulting experience
Additional Information
What we offer:
Flexible and remote cooperation options
International projects with leading global clients
Travels related to international projects
Non-corporate atmosphere
Access* to language classes
Access* to knowledge-sharing initiatives
Access* to private healthcare and life insurance
Access* to multisport card
*The availability and terms of individual benefits may vary depending on the chosen form of cooperation.
Company Description
Software Mind develops solutions that make an impact for companies around the globe. Tech giants & unicorns, transformative projects, emerging technologies and limitless opportunities – these are a few words that describe an average day for us. Building cross-functional engineering teams that take ownership and crave more means we’re always on the lookout for talented people who bring passion and creativity to every project. Our culture embraces openness, acts with respect, shows grit & guts and combines cooperation with enjoyment.
Also open at Software Mind
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