Sr. Back End Developer

Join a fast-paced team building and evolving the services behind the marketplace shopping experience for a major retail brand. This senior backend role offers the opportunity to design and deliver scalable, high-performance systems that support product discovery, catalog and hierarchy management, ranking, and fulfillment capabilities. Responsibilities

• Design, develop, and maintain scalable backend services for marketplace shopping and pre-purchase experiences.
• Contribute to technical architecture and system design for highly distributed, production-scale applications.
• Build and enhance services that support product catalog management, hierarchy, ranking, and re-ranking.
• Develop solutions for marketplace fulfillment options and related customer-facing shopping functionality.
• Collaborate with team members to solve complex technical problems and deliver reliable software from concept through production.
• Participate in design discussions and help make sound technical decisions for critical platform capabilities.
• Work within an agile, fast-moving environment with evolving priorities and requirements.

• 10+ years of experience with Java.
• 10+ years of experience with Spring Boot and microservices development.
• 10+ years of experience designing and working with distributed systems.
• 3+ years of experience with Kafka or event-driven architecture.
• Strong working knowledge of PostgreSQL or other relational databases.
• Demonstrated experience building and supporting large-scale backend applications.
• Strong problem-solving skills and the ability to work independently on complex engineering challenges.
• Clear communication skills and a collaborative approach to technical teamwork.

Preferred Skills

• Experience with marketplace, e-commerce, or retail platforms.
• Familiarity with Spring Cache.
• Experience with GCP or BigQuery.
• Background in performance tuning and optimization.
• Experience owning and supporting production systems at scale.
• Exposure to highly scalable distributed architecture in a customer-facing environment.

Horizontal is committed to fostering a diverse, equitable, and inclusive workplace where different perspectives are valued and everyone has the opportunity to contribute and succeed. We welcome candidates from all backgrounds who share a passion for building great technology and inclusive teams.