Senior Software Engineer, Product

We're looking for a Senior Software Engineer to own features end-to-end across Arena's platform — from understanding the problem, through designing and building the solution, to shipping it, measuring its impact, and iterating. This is a hands-on IC role for someone who writes code every day, cares deeply about what happens after launch, and is excited to shape how people interact with cutting-edge AI.

Responsibilities

Own features from technical scoping through deployment and post-launch iteration — not just build them, but make sure they work; Design and extend schemas, APIs, and business logic to support new product capabilities; Ship high-quality product code across the stack; Incorporate real user feedback — from data, direct user contact, or your own product instincts — to improve what you've shipped; Work closely with ML researchers to turn research services to production, making them consumable for product development; Collaborate across design, product, and engineering to figure out what to build, not just how; Identify and advocate for improvements to development, testing, and deployment practices

Requirements

4+ years of experience in software engineering, with a focus on product development; Experience building user-facing web applications spanning frontend, backend/API, and database — in any stack. You understand the request lifecycle across layers; Clear, concise communication — you explain technical decisions well, distinguish your work from the team's, and proactively share context; Evidence of shipping and iterating — you can describe the full arc of a feature you owned: problem, solution, code, what happened after launch, and what you'd change now; A product engineering identity — you care about whether the thing you built actually worked for users, not just whether the code was clean; Genuine curiosity about AI evaluation and Arena's mission — you've looked at the product and can articulate why this domain matters to you

Nice to have

Familiarity with our stack: NextJS, React, TypeScript, Tailwind, ShadCN, HonoJS, Postgres, Vitest; Experience with Supabase or Vercel's AI SDK; You've shipped without PM or design support — determined what to build by talking to users or looking at data

Benefits

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