Senior Software Engineer - Backend

Fanatics Markets:

Fanatics Markets is the real-money prediction and trading app where you can invest in moments you care about. Built on a secure platform, we let users predict real-world outcomes and trade on events they actually follow, from sports and entertainment to political elections and beyond. Our mission is to redefine how fans engage with the moments and markets that matter most. We’re looking for the right people to help us build the future of prediction markets.

Overview:

This Senior Software Engineer (Backend) role is a senior-level IC with significant ownership over the core trading platform underpinning all FMX operations. You will join a greenfield team building new services in Go, working alongside engineers with deep backgrounds in regulated financial infrastructure.

You will lead by example, establishing best practices for AI-assisted development while building systems that must meet the reliability, latency, and auditability standards of a regulated product.

We're pioneering the use of AI as a code collaborator. We need engineers who have gone beyond experimentation and who actively use Claude Code, Cursor, Codex, GitHub Copilot, or similar tools to ship production code faster while maintaining exceptional quality standards.

Responsibilities:

• Lead the design, development, testing, and deployment of high-performance, fault-tolerant backend services supporting the FMX trading platform.
• Own services and features end-to-end: spec writing → implementation → instrumentation → deployment → monitoring → iteration based on metrics.
• Work within and help modernise a Java codebase while contributing to new service development in Go, Java and Kotlin.
• Contribute to the architecture for order processing, market data distribution, and trade lifecycle management on a regulated product.
• Build and maintain reliable daily reporting pipelines, ensuring data integrity and full audit trails across all trading activity.
• Participate in 24/7 on-call rotations; contribute to SLO definition, alerting strategy, and incident response for mission-critical trading infrastructure.
• Model and manage data for contracts, orders, positions, and settlements with an emphasis on correctness, integrity, and regulatory auditability.
• Collaborate with the Dev