---
title: 'Staff Software Engineer, Product at Arena Intelligence, Inc.'
canonical: 'https://feeny.ai/job/staff-software-engineer-product-arena-intelligence-inc-bay-area-xb7eeqqqtw0h'
type: 'job'
last_seen: '2026-09-11'
---

# Staff Software Engineer, Product at Arena Intelligence, Inc.

- **Company:** Arena Intelligence, Inc.
- **Location:** Bay Area
- **Employment:** full-time
- **Work type:** hybrid
- **Posted:** 2025-12-18
- **Last confirmed live:** 2026-09-11
- **Apply:** https://jobs.ashbyhq.com/arena/7354e079-fd69-4c1a-b9ce-ce99dcf30482/application

**Skills:** Software Engineering, Web Application Development, Data Modeling, API Design, Frontend Architecture, Backend Services, Infrastructure, Deployment Strategy, Technical Decision Making, System Design, AI/LLM Systems, Inference Pipelines, Evaluation Workflows, Model Integration, NextJS, React, TypeScript, Tailwind, ShadCN, HonoJS

> The Staff Software Engineer owns entire product areas at Arena Intelligence, designing and shipping full-stack systems and making high-stakes technical decisions. This hands-on role involves building data models, APIs, and frontend architectures while collaborating with ML researchers to deliver reliable AI evaluati...

## Job description

## About Arena Intelligence

Arena is the platform for evaluating how AI models perform in the real world. Founded by researchers from UC Berkeley's SkyLab, we're on a mission to measure and advance the frontier of AI for real-world use, and to build the foundation for everyone to understand, shape, and benefit from it.

Tens of millions of people use Arena each month to evaluate how frontier systems handle the work they actually do. The preferences they share power the most transparent, rigorous, and human-centered evaluations in AI. Leading AI labs, enterprises, and independent researchers rely on our work and open datasets to understand how models behave in real workflows: agentic coding, creative generation, professional productivity, and beyond. We go beyond leaderboards and decompose what human experience reveals about AI, so models advance toward the work people actually do.

We're a team of researchers, academics, builders, and creatives from UC Berkeley, Google, Stanford, and DeepMind. We seek truth, move fast, and value craftsmanship, curiosity, and impact over hierarchy. We're building a company where thoughtful, curious people from all backgrounds can do their best work together, in an office culture that radiates excellence, energy, and focus.

## 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.

You’ll

- Own product areas end-to-end — from identifying opportunities that aren't on anyone's roadmap, to building conviction, shipping, and driving to measurable outcomes
- Design complete systems: data model, API design, frontend architecture (full-stack) or backend services and infrastructure (backend), and deployment strategy
- Make high-stakes technical decisions under uncertainty — build-vs-buy, monolith-vs-service, when to prototype and when to harden — and be accountable for the outcomes
- Work with ML researchers to turn research services into reliable, product-consumable systems
- 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, and create clarity out of ambiguity
- Navigate cross-functional collaboration with product, design, research, and leadership to align on what matters

You’ll have

- 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. You can design complete systems end-to-end and explain why you rejected alternatives at each decision point. You 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 can go three levels deep on any decision and get more specific, not vaguer.
- Product judgment and autonomous ownership — 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

- We offer competitive compensation and equity aligned to the markets where our team members are based. The base salary range will depend on the candidate’s permanent work location.
- 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.

Arena Intelligence provides equal employment opportunities (EEO) to all employees and applicants for employment without regard to race, color, religion, sex, national origin, age, disability, genetics, sexual orientation, gender identity, or gender expression. We are committed to a diverse and inclusive workforce and welcome people from all backgrounds, experiences, perspectives, and abilities.

## About Arena Intelligence, Inc.

## Company Overview
- **One-liner**: Arena Intelligence, Inc. (formerly LMArena/Chatbot Arena) operates a public, community-driven platform for evaluating large language models through anonymous head-to-head comparisons and voting.
- **Entity Type**: Private (Series A, total $250M funding)
- **Headquarters**: San Francisco, California, United States
- **Founded**: 2025 (company incorporation; platform launched April 2023)
- **Founders**: Wei-Lin Chiang, Anastasios N. Angelopoulos, Ion Stoica

## Core Business
- **Primary industry**: AI evaluation and research infrastructure
- **Target customers**: AI labs (OpenAI, Google DeepMind, Anthropic, DeepSeek), enterprises, researchers, and the general AI community (B2B and B2C)
- **Mission**: Fuel the world’s most trusted AI evaluation platform, using real-world community votes to benchmark model performance

## Products & Services
- **LMArena Platform**: Public web-based platform where users enter prompts for two anonymous models, vote on the better response, and then see the models’ identities. Supports text, vision, web dev, search, video, and image modalities. Over 50 million votes collected.
- **Max (Model Router)**: An intelligent orchestrator that routes each user prompt to the most capable model for that specific prompt, powered by 5+ million real-world votes.
- **Enterprise Evaluation Product**: Launched September 2025, provides rigorous, reproducible evaluations for AI labs and enterprises, generating actionable feedback on model performance.

## Market Standing
- **Valuation/Market Cap**: Not publicly disclosed
- **Key Metric**: $100M annualized revenue run rate as of June 2026 (achieved within 8 months of enterprise offering launch)
- **Total Funding**: $250M (Seed $100M led by Andreessen Horowitz and UC Investments in June 2025; Series A $150M led by Felicis and UC Investments in January 2026)
- **Notable Investors/Partners**: Felicis, UC Investments, Andreessen Horowitz, The House Fund, LDVP, Kleiner Perkins, Lightspeed Venture Partners, Laude Ventures
- **Growth Signals**: Community grew 25x in one year; 50 million votes, 400+ model evaluations, 145k open-source battle data points; operates in 5 countries (US, Germany, UK, UAE, Canada); headcount of 49 with +10.5% monthly growth

## Competitive Advantages
- **Community-driven data**: Trusted by major AI labs for real-world, reproducible evaluations; 10M+ community members contribute diverse prompts and votes
- **First-mover & brand**: The de facto public leaderboard for LLM comparison; used for pre-release model testing (e.g., DeepSeek R1, GPT-5 "summit", Gemini 2.5 Flash Image "Nano Banana")
- **Open science**: Academic partnerships program funding independent research on AI evaluation methodology
- **Revenue velocity**: Achieved $100M ARR in under a year from enterprise launch, indicating strong product-market fit

## Strategic Focus
- Scale the platform with new features and modalities (video, search, web dev)
- Deepen enterprise offerings and model routing capabilities (Max)
- Expand academic partnerships to advance the science of AI evaluation
- Continue to serve as the gold standard for real-world model performance benchmarking

## Why Work Here
- **Culture**: Fast-moving, research-driven startup with roots at UC Berkeley; emphasis on community, open source, and rigorous science
- **Team**: 49 employees, 41% technical (Data Engineers, ML Scientists, ML Engineers, Software Engineers), with talent from top AI labs and universities (Berkeley RISE Lab, Google, Apple)
- **Growth**: High-growth environment (revenue run rate doubled rapidly, headcount growing ~10% monthly)
- **Location**: Headquarters in San Francisco (2261 Market St., Ste 85064); offices also in SF (two additional locations). Likely hybrid/office-based given SF HQ and local employee concentration.
- **Perks**: Not explicitly listed, but typical for VC-backed startup (equity, competitive comp, impact on foundational AI infrastructure)

## Sources
1. [arena.ai](https://arena.ai/)
2. [arena.ai/blog/series-a](https://arena.ai/blog/series-a/)
3. [linkedin.com/company/arenaai](https://www.linkedin.com/company/arenaai)
4. [jobs.ashbyhq.com/arena](https://jobs.ashbyhq.com/arena)

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