Senior Software Engineer (Backend, Payments)

Join our Payments team as a Senior Software Engineer, where you'll be responsible for building, scaling, and evolving the payments infrastructure that powers every transaction across the Collectors ecosystem. You'll work across backend APIs and modern frontend surfaces, partnering with product, design, and cross-functional engineering teams to deliver reliable, scalable, and secure payment experiences. This is a high-impact, high-visibility role that will have a direct influence on architecture decisions, gateway integrations, and the quality of everything that ships.

• Concevoir, mettre en œuvre et maintenir des intégrations avec plusieurs fournisseurs de passerelles de paiement, en construisant des abstractions propres qui minimisent les perturbations lors de l'ajout ou du remplacement de passerelles.
• Développer des services de paiement backend et des API en C#/.NET tout en construisant des expériences client intuitives en React, Svelte et TypeScript qui alimentent le processus de paiement.
• Appliquer les meilleures pratiques PCI-DSS et les modèles de conception résilients pour garantir un traitement des paiements sécurisé et fiable à grande échelle.
• AI-first engineer. You build with AI tooling across the SDLC — from planning and code generation to review and debugging. You have a clear, practiced point of view on how AI raises the quality bar and accelerates delivery
• Security-minded. You treat payment security as a first-class engineering concern, not an afterthought
• Influential communicator. A strong written and verbal communicator with sharp analytical and troubleshooting instincts — you align engineers, product partners, and stakeholders without direct authority, make crisp calls, and bring people with you
• Frontend range in React, Svelte, and TypeScript. You build clean, responsive payment UIs and understand the nuances of state management, form handling, and secure client-side data flows
• 6+ years engineering experience. You have a track record of designing, shipping, and scaling products that have measurable business impact. Ideally 2+ years operating as a Senior IC or equivalent technical leadership level at a high-growth company or a scaled consumer platform
• Familiar with Agile/Scrum methodologies. You're comfortable working in iterative delivery cycles, participating in sprint planning, and adapting quickly to changing priorities
• Deep backend expertise in C# (.NET). You’re comfortable owning complex API surfaces, async patterns, and data consistency in distributed systems
• Passion for collecting is a plus
• Payments or fintech experience. You understand gateway integrations, idempotency, webhook reliability, tokenization, and PCI compliance in production environments
• Distributed-systems depth. You’ve designed and operated microservices and Kafka-based event-driven architectures, run workloads on Kubernetes, and know your way around the AWS ecosystem
• Observability-first mindset. You instrument what you ship using Datadog or similar tools. You're comfortable building dashboards, setting up monitoring/alerting, and using distributed tracing to debug production issues
• Strong fundamentals working with databases and data modeling, both relational (e.g. PostgreSQL) and NoSQL (e.g. DynamoDB). You're comfortable designing schemas, writing efficient queries, and choosing the right storage layer for the problem
• Bias for ownership. You have an extreme ownership mindset and will wear any hat required to get the job done. You thrive in a fast-moving, self-directed environment — you set the bar, hold it, and take full accountability for outcomes