• Develop and maintain backend services for card payment processing using PHP (Symfony) and Golang. • Integrate and support payment service providers (PSPs) and acquirers (Adyen, Checkout.com, JP Morgan Chase, etc.) • Design and implement scalable, event-driven architectures for high-load payment systems • Write clean, testable code with comprehensive unit and functional test coverage • Optimize database queries and data models for OLTP workloads (MySQL, MongoDB) • Collaborate with the team on system design, code reviews, and technical decisions • Ensure system observability and troubleshoot issues using ELK stack • Participate in CI/CD pipeline improvements and deployment processes

• Own backend features end-to-end: scope → design → implement → test → ship → observe • Build production-grade web services and APIs (primarily in PHP with Symfony) • Write efficient SQL (MySQL) and use Doctrine ORM effectively; tune queries and indexes • Improve reliability and performance through thoughtful design, profiling, and instrumentation • Partner with Product and Design to turn requirements into simple, lovable solutions • Raise the bar on engineering standards, tooling, observability, and developer experience • Mentor peers (and be open to being mentored); give and receive clear, actionable feedback

• Lead the technical direction of projects, making high-level architectural decisions for full-stack applications that integrate AI services • Design and build robust backend services (Python) and intuitive, interactive frontend interfaces (React/Vue/Angular) that visualize complex data and AI interactions • Architect and maintain data processing pipelines, agentic workflows, and LLM integrations to solve real-world client problems • Foster a culture of excellence by performing rigorous code reviews, mentoring junior and senior developers, and driving the adoption of best practices • Partner closely with Product Management, Design, and QA to translate complex requirements into technical roadmaps and deliverable software • Evaluate system performance across the full stack, identifying bottlenecks in both the frontend rendering and backend AI inference layers to ensure scalability and reliability • Stay ahead of the curve on the latest AI trends (e.g., SLMs, Agentic AI, Multimodal models) and web technologies, advising stakeholders on feasibility and implementation

• Wspólnie z londyńskim partnerem, rozwijamy platformę opartą o AI, która mierzy emisje CO₂ od samego źródła • Angażują się w projekt i dbają o jakość swojej pracy