Senior Kotlin Engineer

Summary

Join CookUnity, a rapidly growing food marketplace, as a Senior Backend Engineer on the Revenue Engine Squad. You will be responsible for designing and developing scalable backend systems for payment processing, pricing, and refunds, ensuring a smooth and secure financial infrastructure. This role requires strong expertise in payment systems, payment processing, and service-oriented architecture, with a focus on building robust services that empower the marketplace and enhance the customer experience. You will collaborate closely with cross-functional teams, including Product, Marketing, Finance, and Legal, to ensure compliance and fraud prevention. This is an opportunity to tackle complex engineering challenges and have a direct impact on the evolution of a fast-growing marketplace.

Requirements

• 5+ years of experience in backend development, with expertise in Kotlin, Java, and SQL databases (PostgreSQL or MySQL)
• Strong knowledge of payment processing systems and experience integrating with third-party payment providers like Stripe, PayPal
• Experience designing and building scalable cloud-based architectures and distributed systems
• Expertise in service-oriented architectures, API design, and microservices development
• Strong knowledge of database design, implementation, and query optimization
• Experience with system performance monitoring, logging, and observability
• Ability to write clean, maintainable, and testable code
• Advanced level of English with strong communication skills, both verbal and written

Responsibilities

• Design, develop, and maintain scalable backend services for payment processing, pricing, and refunds
• Integrate payment gateways and 3rd party integrations
• Optimize payment success rates by improving retry mechanisms, fraud detection, and error handling
• Develop and implement features to support promotions, subscriptions, and order finalization workflows
• Work on multi-currency support and international payment processing
• Define and uphold engineering best practices in security, scalability, performance, and code quality
• Improve the maturity of our technical stack through engineering best practices and process automation
• Monitor and enhance system performance
• Participate in code reviews, mentorship, and technical decision-making
• Collaborate with cross-functional teams including finance, legal, and security to ensure compliance and fraud prevention

Preferred Qualifications

• Experience working in high-transaction volume eCommerce or fintech environments
• Knowledge of PCI compliance, fraud detection, and payment security best practices
• Experience with Saga pattern and orchestration frameworks such as Temporal to manage distributed transactions and workflows
• Experience with event-driven architectures and message queues (e.g., Kafka, RabbitMQ)
• Experience in subscription billing models and recurring payments
• Prior experience working in a fast-paced startup environment

Benefits

• Get paid in USD. Whatever your choice! We use Deel to make things easier for you!
• Work remotely: design the life that you want
• Enjoy 15 business days of vacation each year from the start date
• Healthcare Benefit: Monthly stipend to use in your preferred healthcare provider
• 16 fully paid Argentinean holidays
• Compassionate Leave: 3-5 days each time the need arises
• Family leave of 12 weeks for primary caregiver and 6 weeks for secondary caregiver, fully paid
• Personalized English coach
• Customize the benefits that suit your needs! Access a range of perks tailored to you, including learning opportunities, wellness memberships, delivery apps, and more through our comprehensive benefit platform
• 5- year Sabbatical: After 5 years with CookUnity, you get a 4-week paid sabbatical