Senior Backend Developer

Who We Are Yuno is building the payment infrastructure that enables all companies to participate in the global market. Founded by a team of seasoned experts in the payments and IT industries, Yuno provides a high-performance payment orchestrator that connects businesses to 300+ payment methods worldwide through a single integration. Our technology offers companies access to leading payment capabilities, allowing them to engage customers confidently and maintain global business operations with seamless payment integrations. We power high-performing teams at brands like InDrive, McDonald's, Rappi, and Viva Aerobus across 80+ countries. The Role We are looking for a Backend Developer to join the Checkout Team, one of the most critical squads at Yuno, responsible for the core transaction processing engine that powers our checkout flows at scale. You will design and build the systems that handle millions of payment transactions globally, working with a world-class team of engineers in a fast-paced, high-impact environment. Your Challenge at Yuno Design, build, and evolve high-performance backend services and APIs in Kotlin and Spring Boot, engineered for reliability, low latency, and massive scale. Own the full lifecycle of features, from technical design and implementation to monitoring and ensuring correct operation in production. Develop and maintain checkout payment flows, including authorization, capture, refunds, reversals, and partial payments across multiple payment providers and regions. Architect and implement resilient microservices using event-driven patterns (Kafka, queues) to handle asynchronous payment processing with zero data loss. Strengthen and expand the integration framework that connects Yuno to PSPs, acquirers, and payment gateways across countries and complex payment rails. Apply OWASP principles and engineering best practices to ensure excellence in security, privacy, and PCI-DSS compliance. Collaborate with Product, Compliance, and Business teams to translate real payment problems into elegant, scalable technical solutions. Participate actively in code reviews, architecture decisions, and technical discussions that shape the direction of the platform. Contribute to a culture of technical excellence, writing clean, well-tested, production-ready code with a strong focus on quality. Skills You Need Minimum Qualifications 4+ years of professional backend development experience. Kotlin Strong proficiency in Spring Boot Deep expertise with payment processing concepts Solid understanding of microservices architectures Experience building and operating Proficiency with relational databases (PostgreSQL or similar) and data modeling for financial systems. Experience with containerization and cloud infrastructure (Docker, Kubernetes, AWS or GCP). Strong command of unit, integration, and contract testing practices. Fluent written and verbal communication in English. Nice to Have Experience in a fintech, neobank, or payment orchestration environment. Familiarity with PCI-DSS, PSD2, or 3DS authentication frameworks. Hands-on experience with Kafka or other event streaming platforms. Knowledge of network tokenization, smart routing, or payment optimization strategies. Experience with observability tooling (Datadog, OpenTelemetry, distributed tracing). Prior work at a high-growth startup operating across multiple markets. Tech Stack Languages Kotlin (primary), Java Frameworks Spring Boot, Spring WebFlux Messaging Apache Kafka, SQS Databases PostgreSQL, Redis Infrastructure AWS, Kubernetes, Docker, Terraform Observability Datadog, OpenTelemetry CI/CD GitHub Actions, ArgoCD Version Control Git / GitHub