2 months ago
Barcelona, SpainSenior
Responsibilities
- Build and evolve the core payment platform.
- Design new services and payment-provider integrations from architecture through production.
- Improve transaction processing, routing, and webhook infrastructure.
- Participate in architectural decisions and technical discussions.
- Review code, share knowledge, and maintain a high engineering standard.
- Collaborate closely with the Python/TypeScript Connector team.
- Maintain software quality, production reliability, testing, logging, metrics, tracing, and observability.
Requirements
- Strong .NET expertise with deep knowledge of C# and .NET 8/9.
- Solid experience with ASP.NET Core, asynchronous programming, highly concurrent applications, Minimal API, Hosted Services, and Dependency Injection.
- Experience building distributed systems and understanding event-driven architecture, idempotency, Inbox/Outbox patterns, reliable message delivery, microservices, and distributed transactions.
- Production experience with Apache Kafka, including consumer groups, at-least-once delivery, manual offset commits, and idempotent consumers.
- Experience with PostgreSQL, Dapper, SQL performance optimization, Redis or Valkey, caching strategies, and Sentinel or Redis Cluster.
- Experience with Docker, Docker Swarm or Kubernetes, and production deployments.
- FinTech experience with payment platforms, PayIn/PayOut flows, webhooks, callbacks, payment routing, cascade retry, HMAC signatures, replay-attack protection, or PCI DSS requirements is preferred.
- Experience with unit and integration testing, structured logging, metrics, distributed tracing, and observability.
- Nice-to-have experience with Lua/LuaJIT, OpenAPI-first development, openapi-generator, Python or TypeScript, Git Submodules, and dynamic configuration through event buses.
- Comfort using AI-assisted development tools such as Cursor, Claude Code, or GitHub Copilot while maintaining ownership of produced code.
Benefits
- Remote, full-time position.
- Opportunity to build core infrastructure for a modern payment platform used in production.
Tech Stack
Categories
About OnHires
OnHires is a global recruitment and staffing agency that helps companies hire tech and creative talent, with focus areas including AI, Web3, blockchain, and DeFi. It provides IT recruiting and HR consulting services for startups and established firms, covering roles from engineers and designers to executives. Founded in 2020 and headquartered in Sheridan, Wyoming, OnHires is privately held.