Staff Software Engineer, Product

About the role

We're looking for a Staff Software Engineer to own entire product areas at Arena — identifying what to build, designing and shipping the solution, driving it to measurable outcomes, and raising the bar for the team along the way. This is a hands-on IC role. You are the architect, not the delegator. You write code, design systems, and ship product — and you have a track record of doing this repeatedly with clear, attributable impact.

Design complete systems

• Data model
• API design
• Frontend architecture (full-stack)
• Backend services and infrastructure (backend)
• Deployment strategy

Make high-stakes technical decisions

• Build-vs-buy
• Monolith-vs-service
• When to prototype and when to harden

Ship and iterate

• You don't hand off after v1. You measure, course-correct, and drive to sustained impact

Raise the technical and product quality bar on the team

• Introduce practices others adopt
• Unblock teammates
• Create clarity out of ambiguity

Navigate cross-functional collaboration

• With product, design, research, and leadership to align on what matters

Technical Depth and Product Judgment

• 8+ years of experience in software engineering, with a focus on product development
• Deep experience building web applications spanning data model, API, frontend architecture, and deployment
• Can design complete systems end-to-end and explain why you rejected alternatives at each decision point
• Can explain how your architecture decisions shaped the product's capabilities and measurably improved product quality or team velocity
• A track record of repeated, attributable impact — multiple projects across different roles or companies where you can quantify outcomes (revenue, engagement, efficiency) and the impact sustained after you moved on
• Personal technical depth, not delegation — you are the architect. You've dealt with real performance issues: slow queries, N+1 problems, caching, transaction isolation
• You've identified opportunities, validated them with evidence, built buy-in, shipped, and the bet paid off. You know when to prototype, harden, or kill work
• Clear, persuasive communication — you build buy-in across engineering, product, and leadership. You create clarity for others, not just yourself
• Genuine conviction about AI evaluation and Arena's mission — you can articulate why this domain matters and where the product should go

Bonus Points

• Production experience with AI/LLM systems — inference pipelines, evaluation workflows, model integration, or AI-powered product features
• Familiarity with our stack: NextJS, React, TypeScript, Tailwind, ShadCN, HonoJS, Postgres, Vitest
• Experience with Supabase or Vercel's AI SDK
• You've raised the bar on a team with measurable before/after — introduced practices, tools, or standards that others adopted

Our Tech Stack

• NextJS
• React + TypeScript
• Tailwind + ShadCN
• HonoJS
• Postgres
• Vitest

What we offer

• Competitive compensation and equity aligned to the markets where our team members are based
• Comprehensive health and wellness benefits, including medical, dental, vision, and additional support programs
• The opportunity to work on cutting-edge AI with a small, mission-driven team
• A culture that values transparency, trust, and community impact

Come help build the space

• Where anyone can explore and help shape the future of AI

Equal Employment Opportunity

• We are committed to a diverse and inclusive workforce and welcome people from all backgrounds, experiences, perspectives, and abilities