Senior Backend Developer (Services)

payabl. is a licensed financial company specializing in global payments and multi-currency banking solutions. It offers a unified platform, payabl.one, providing global financial services with principal membership in card schemes.

• 5+ years of backend development experience with strong Python expertise
• Deep knowledge of AsyncIO and FastAPI
• Experience building non-blocking, high-reliability microservices
• Strong experience with relational databases such as MySQL and PostgreSQL
• Solid understanding of API design and third-party integrations
• Experience implementing webhooks, callbacks, and retry strategies
• Strong testing practices including unit and integration testing
• Ability to work with legacy systems and migrate them into modern architectures
• Strong analytical and problem-solving skills
• Ownership mindset and ability to work autonomously within a defined architecture

Nice to Have:

• Experience with PHP, Perl, or JavaScript
• Familiarity with Kafka, Redis, or event-driven architectures
• Exposure to CI/CD pipelines, Docker, and Kubernetes
• Experience in fintech, payments, or e-commerce domains
• Knowledge of 3DS, tokenization, or payment gateway integrations
• Proven experience migrating systems across technologies or paradigms

• Design, build, and maintain high-performance Python microservices using FastAPI and AsyncIO
• Analyze legacy systems and extract business logic into modern architectures
• Refactor and migrate existing modules into clean, scalable, and maintainable services
• Ensure system reliability through idempotency, fault tolerance, and robust error handling
• Design and integrate external APIs handling edge cases, retries, and failures
• Implement and manage webhooks, callbacks, and complex retry mechanisms
• Write high-quality unit and integration tests
• Collaborate with cross-functional teams to ensure service stability and performance
• Contribute to architectural discussions and continuous system improvements
• Take ownership of services end-to-end, from design to production