Senior Kotlin developer (m/f/d) - Team Payments

at  Flix

We’re looking for a motivated and driven Senior Kotlin Engineer who will help us shape our Payments team, drive the company to the next level, and have the most direct influence on our success.
You will be part of the customer-facing Payments Product Engineering team, focusing on providing an easy and intuitive checkout experience. Most of our services are written in PHP with a React.js front-end. We are transitioning to Kotlin for new services and need your expertise.
Our payments team consists of three back-end engineers, two front-end engineers, an Engineering People Manager, and a Product Owner. We aim to achieve high progression and payment authorization rates, improve payment efficiency and revenue protection, and ensure data reliability. We are integrating more local payment methods in various markets and solving numerous engineering challenges.
Join us in Team Payments to deliver a top-of-the-line, seamless, and secure payment experience for green and smart mobility worldwide.

YOUR PROFILE – READY TO HOP ON BOARD

• Proficiency in Kotlin, including modern features and best practices.
• Familiarity with JVM-based technologies, including libraries and tools.
• Experience with PHP and Symfony (or be a fast learner and be open to working with it).
• Knowledge of designing and implementing microservices, including service discovery, load balancing, and inter-service communication.
• Strong analytical and problem-solving abilities to debug and optimize complex systems.
• Knowledge of security best practices for backend development, including OAuth, JWT, and SSL/TLS.
• Experience with containerization (Docker) and orchestration (Kubernetes).
• Experience with cloud services (AWS is a plus).
• Good SQL experience and a good understanding of an ORM’s internals.
• Experience with in-memory data stores like Redis for caching and session management.
• Good knowledge with CI/CD pipelines and tools.
• Experience with distributed messaging systems (Kafka).
• Proficiency in writing tests (e.g., unit, integration, and end-to-end tests).
• Understanding of DevOps principles and experience with infrastructure as code (e.g., Terraform, Ansible).
• Expertise in designing and developing RESTful APIs.
• Familiarity with Agile practices, such as Scrum or Kanban.
• Bachelor/Master in Computer Science, Information Systems, or relevant industry experience.
• Fluent in English.
• It’s a plus if you bring, experience with Payment Systems.
• You are a team player, love to take ownership, lead initiatives and work in a collaborative environment.
• You have good written and verbal communication skills to effectively convey technical ideas and work with cross-functional teams.
• You are passionate about mentoring and helping your peers grow.
  We encourage you to apply even if you don’t meet every single requirement listed. We value diverse experiences and perspectives that may not perfectly align with the job description but can still bring valuable contributions to our team. If you’re passionate about this role, we want to hear from you. Your unique background might be just what we’re looking for!

• Design technical solutions that serve millions of users.
• Decouple our large systems into independent services and self-contained systems.
• Optimize databases with hundreds of millions of rows.
• Write SOLID, maintainable, flexible, testable, and tested code.
• Analyze, propose, and drive technology improvements.
• Support our CI/CD environment and produce a positive impact with each release.
• Be part of an autonomous cross-functional team, responsible for the payments product from concept to implementation.
• Work closely with team members through pair and mob programming, code reviews, and testing.