Senior / Staff Software Engineer, Backend (Fantasy Sports)

• Build and own core fantasy systems: leagues, rosters, drafts, waivers, trades, matchups, and scoring from data model to API
• Scale real-time scoring to ingest live stat feeds and deliver changes to millions of rosters with low latency
• Ship features end-to-end with designers and mobile/web engineers
• Monitor production health, profile systems, and plan capacity ahead of peak seasons
• At Staff level: own system architecture, raise engineering standards through design and code review, mentor other engineers

About Sleeper Sleeper is on a mission to connect people over sports through games and community. As one of the fastest-growing platforms in the fantasy sports and real-money gaming space, we’re redefining how sports fans engage—whether it’s through season-long leagues, pick’em contests, or real-time interactions with friends. Our team is lean, passionate, and product-driven. We obsess over user experience and believe that building delightful, fast, and reliable products is the best way to grow. Backed by some of the most respected investors in Silicon Valley, including Andreessen Horowitz and General Catalyst, we're building the future of sports engagement.

About the Role We're hiring Senior and Staff Backend Engineers for our fantasy sports product — season-long leagues, drafts, waivers, trades, matchups, live scoring, and the league chat that holds it all together, across NFL, NBA, and more. Fantasy is where Sleeper started, and it remains the core of the platform. The work is backend engineering at real scale on a calendar that doesn't move. Millions of users are active at once on game days, live scoring has to reach every roster quickly and correctly, and drafts run in real time. Traffic peaks hard, and the systems behind it have to be fast, reliable, and right. You'll own systems and features end to end: the data model, the service behind it, and the API contract with our mobile and web teams, working directly with designers. Engineers make product decisions here, not just implement them.

What You’ll Do

• Build and own the core systems behind fantasy — leagues, rosters, drafts, waivers and trades, matchups, and scoring — from data model to API.

• Scale real-time scoring: ingest live stat feeds and deliver every change to millions of rosters and open app sessions with low latency and correct results.

• Ship features end to end with designers and our mobile and web engineers, from a rough idea to something in millions of users' hands.

• Keep production healthy: monitoring, profiling, and capacity planning ahead of the season, so bottlenecks get found before Sunday finds them.

• At Staff: own the architecture of the systems you work in, raise the bar through design and code review, and help other engineers ship at scale.

Who You Are

• 5+ years of backend engineering. For Staff, 8+ years and a track record of owning the architecture of systems at this scale.

• You've built and operated consumer products with millions of users, and you understand what your code does in production at that scale.

• You've shipped features end to end — not only infrastructure.

• Deep in distributed systems: data modeling, caching, queues, and the correctness questions that come with real-time fan-out.

• Strong in at least one backend language — Elixir, Go, Java, Python, Rust, Node, or similar.

• You can go deep on your own work: what you decided, what you'd do differently, and where your contribution ended and the team's began.

• You're a sports fan. Best case, you play fantasy — you'll build a better product if you know what it's like to lose a matchup on Monday night.

• Based in the San Francisco Bay Area or New York City, working hybrid.

Why Join Sleeper?

• Massive Impact – Your work will touch millions of users and help shape the next generation of sports entertainment.

• High Ownership – We trust our engineers to make high-leverage decisions and drive meaningful outcomes.

• Startup Agility – Move fast, ship often, and see your work in the hands of users quickly.

• Culture-First Team – We’re a team of builders, thinkers, and sports lovers who value humility, collaboration, and having fun along the way.

What We Offer

• Competitive salary $180,000–$300,000/year (level and base set by experience; not inclusive of stock options and benefits)

• Equity

• Comprehensive medical, dental, and vision insurance

• 401(k)

• Generous PTO and a hybrid work policy (San Francisco Bay Area or New York City)

• Opportunities for fast career growth in a high-impact role

• A small, focused team where your contributions truly matter

Our Hiring Philosophy Sleeper believes in quality over quantity, and intentionally keeps our team small as a result. In past roles, we found it very hard to make a big impact when companies grow too large in size, which has a detrimental effect on the product and the impact any single individual can have. Our team includes designers, engineers, product experts, and finance & operation focused on one thing — connecting people over sports. We believe in fair and equitable pay. Certain locations in the United States require job postings to include a reasonable estimate of the base salary range and/or a general description of benefits and other compensation applicable to the role.

Competitive salary plus benefits including Medical, Dental, PTO, 401k. Please note that The salary range for this role ($180,000 to $300,000 per year salary) takes into account a wide range of factors that are considered in making compensation decisions including, but not limited to, skill sets; experience and training; licensure and certifications; and other business and organizational needs. The policy of Sleeper is to provide equal employment opportunities to all applicants and employees without regard to race, color, creed, religion, sex, sexual orientation, gender identity, marital status, citizenship status, age, national origin, ancestry, disability, veteran status, or any other legally protected status and to affirmatively seek to advance the principles of equal employment opportunity. Sleeper is committed to being an Equal Opportunity Employer and offers opportunities to all job seekers, including job seekers with disabilities. If you are a qualified individual with a disability or a disabled veteran, you may request a reasonable accommodation if you are unable or limited in your ability to use or access the Company’s career webpage as a result of your disability. You may request reaso

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