Staff Software Engineer - FMX

About 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 Staff Software Engineer role is an individual contributor position with technical leadership and significant ownership across our full stack: the web application customers use to interact with our product and the backend systems that power it. You'll combine hands-on engineering with responsibility for shaping architecture, setting technical direction, and enabling engineers across teams to deliver effectively.

Whether your deepest expertise is in frontend or backend engineering, you'll apply that strength across the platform while making meaningful contributions on the other side of the stack. Joining a product at an exciting early stage, you'll help define its technical foundations, identify the highest-impact engineering challenges, and turn ambiguous problems into clear plans that balance customer needs, delivery speed, and long-term reliability.

Your impact will extend beyond the systems you build. You'll lead complex initiatives spanning teams, mentor engineers, and establish practices that improve engineering quality and effectiveness. You'll also shape our approach to AI-assisted development while building systems that can handle millions of events daily.

On the engineering side, we're pioneering the use of AI as a code collaborator. We need engineers who have gone beyond experimentation — who actively use Claude Code, Codex, GitHub Copilot, or similar tools to ship production code faster while maintaining exceptional quality standards, and who can help others adopt these workflows responsibly and effectively.

Responsibilities:

• Set technical direction for major areas of the Markets platform, aligning architectural decisions with product strategy and guiding their implementation across teams
• Lead the design and delivery of complex, scalable systems and customer experiences, contributing hands-on in React, Next.js, and TypeScript or backend services in Go, while making meaningful contributions across the stack
• Identify and resolve ambiguous engineering problems spanning team or system boundaries, turning them into clear proposals, delivery plans, and measurable outcomes
• Own critical initiatives end-to-end, from discovery and technical specifications through implementation, instrumentation, deployment, monitoring, and iteration
• Partner with product, design, platform, and infrastructure teams to make informed tradeoffs across customer experience, accessibility, performance, security, reliability, and delivery speed
• Define architecture and integration patterns for frontend applications, backend APIs, and event-driven systems, with particular attention to correctness in markets, orders, and transactions
• Guide the design of experimentation capabilities, including feature flags and A/B tests, so teams can validate ideas quickly and safely
• Anticipate scaling constraints, reliability risks, and technical debt; build alignment on pragmatic improvements and drive them through to completion
• Raise engineering standards through design reviews, code reviews, testing strategies, observability, and safe deployment practices
• Mentor engineers and develop technical leaders, helping teams make sound decisions and solve problems independently
• Establish and evolve standards for AI-assisted development, including appropriate use cases, review expectations, security safeguards, and validation strategies
• Measure and improve engineering effectiveness, sharing tools and practices that increase delivery speed without compromising quality
• Lead through influence in an early-stage product environment, creating clarity, unblocking teams, and establishing ways of working that support growth

Qualifications:

• Substantial experience building and operating highly scalable production systems, with demonstrated impact at Staff level or equivalent scope, including technical leadership across teams or major platform areas
• Deep expertise in either user-facing web applications built with JavaScript/TypeScript and React or backend services built with languages such as Go, Java, or Python, alongside the ability to reason across the full stack. If you're frontend-strong, you don't need to arrive fluent in Go, but you should be comfortable engaging with backend architecture and system tradeoffs
• A track record of setting technical direction and delivering complex initiatives from ambiguous requirements through to measurable production outcomes
• Strong architectural judgment, including the ability to assess tradeoffs, establish clear system boundaries, and evolve systems as product requirements and scale change
• Experience shaping React architecture, component-driven development, and modern state management using tools such as Next.js, TanStack Query, Tailwind, or Zustand; or deep backend experience with data modeling, distributed systems, and event-driven architecture using technologies such as Postgres and Kafka/PubSub
• Deep knowledge of your primary language's features, idioms, and best practices, with experience establishing standards adopted beyond your immediate team
• Strong understanding of performance, reliability, and security, including responsive design and accessibility on the frontend or scalability, observability, data integrity, and failure handling on the backend
• Experience defining API contracts and collaborating across product, platform, and infrastructure teams to deliver reliable systems
• Experience shaping CI/CD pipelines, testing strategies, and safe deployment practices across services or applications
• Demonstrated ability to lead through influence, build alignment across teams, and communicate technical decisions clearly to engineers and non-technical stakeholders
• A track record of mentoring engineers, strengthening technical decision-making, and increasing the effectiveness of others
• Demonstrated experience using AI tools such as Claude Code, Codex, Cursor, or Copilot to ship production code, with sound judgment about their limitations and appropriate validation
• Specific examples of improving development workflows, with evidence of their impact on delivery speed, quality, or engineering productivity
• A team-first approach, with the judgment to move between strategic technical work and hands-on delivery according to the needs of the product
• Ability to create clarity in a high-growth environment where priorities evolve and decisions must be made quickly
• Strong cross-functional collaboration skills, including experience aligning teams and navigating dependencies within large enterprise environments

You don't need to tick every box — deep strength in one area, demonstrated technical leadership, and a willingness to learn go a long way.

Preferred Qualifications:

• Previous experience shaping technical foundations in early-stage or high-growth startup environments
• Experience with real-money transaction systems, including financial correctness, auditability, and regulatory requirements
• Experience developing technical roadmaps or leading architectural changes adopted across multiple teams
• Background in building developer tools or improving engineering productivity at scale
• Experience establishing AI-assisted engineering practices across teams
• Contributions to open-source projects or the technical community
• BSc in Computer Science or a related field

Depending on the role, your interview and onboarding experience may include in-person components, such as onsite interviews or Launching into Better: LIVE—a multi-day cultural immersion in New York City for full-time, non-seasonal hires. These sessions are designed to build connections and bring our culture to life, though specific travel and participation requirements will be confirmed based on your role and location. Your recruiter will provide clear guidance at each stage of the process.

Ready to build the future of sports trading? If you possess some of these skills but not all of them, we still encourage you to apply! Please note that visa sponsorship is not available for this position. We are open to fully remote candidates based in the United Kingdom. Remote employees may also be eligible for a home office setup stipend.

Find Jobs in United Kingdom on Arbeitnow