Backend Developer
remoteMillbrae (CA)
About the role
About US:
Xsolla is a global commerce company with robust tools and services to help developers solve the inherent challenges of the video game industry. From indie to AAA, companies partner with Xsolla to help them fund, distribute, market, and monetize their games. Grounded in the belief in the future of video games, Xsolla is resolute in the mission to bring opportunities together, and continually make new resources available to creators. Headquartered and incorporated in Los Angeles, California, Xsolla operates as the merchant of record and has helped over 1,500+ game developers to reach more players and grow their businesses around the world. With more paths to profits and ways to win, developers have all the things needed to enjoy the game. For more information, visit Launch, monetize, and scale with Xsolla tools and services.
About the Role:
We're looking for an experienced Backend Developer to maintain and enhance our payment processing platform that handles card transactions at scale. You'll work with payment gateways, optimize transaction flows, and ensure system reliability.
Key Responsibilities:
- Develop and maintain backend services for card payment processing using PHP (Symfony) and Golang.
- Integrate and support payment service providers (PSPs) and acquirers (Adyen, Checkout.com, JP Morgan Chase, etc.)Design and implement scalable, event-driven architectures for high-load payment systems
- Write clean, testable code with comprehensive unit and functional test coverage
- Optimize database queries and data models for OLTP workloads (MySQL, MongoDB)
- Collaborate with the team on system design, code reviews, and technical decisions
- Ensure system observability and troubleshoot issues using ELK stack
- Participate in CI/CD pipeline improvements and deployment processes
Required Qualifications:
- 3+ years of backend development experience with PHP and/or Golang in production environments
- Hands-on experience with card payment processing and PSP/acquirer integrations
- Understanding of payment flows: authorization, capture, refunds, chargebacks, and reconciliation
- Strong knowledge of OOP principles, design patterns, and clean architecture
- Proficiency in SQL, database design, and performance optimization
- Experience with message queues (RabbitMQ, Kafka) and caching layers (Redis)
- Solid understanding of algorithms, data structures, and their practical application
- Experience writing unit and integration tests
Nice to Have:
- Knowledge of PCI DSS compliance requirements and secure payment data handling
- Understanding of 3D Secure (3DS) authentication protocols
- Experience with tokenization and payment security best practices
- Knowledge of Apple Pay and Google Pay integration principles
- Experience with Kubernetes and Google Cloud Platform
- Familiarity with ELK stack for monitoring and logging
- Previous work with high-load, mission-critical systems
- Frontend development experience with Angular
- Tech Stack
Backend: PHP 8 (Symfony, Doctrine), Golang Databases: MySQL, MongoDB, Redis Infrastructure: Docker, Kubernetes, GCP, RabbitMQ, ELK
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