Arena

2 weeks ago

Backend Engineer

✓ Verified Job

Canonical indexed version, validated from employer's careers page.

Source: Company careers pageValidated by: Fursa AI

Last checked: 16 hours agoStatus: Live

Job Summary

Build and ship low-latency, reliable backend APIs and services that turn Arena’s AI evaluation systems into enterprise-ready products. Own usage metering, billing integration, authentication, RBAC, multi-tenancy, audit logging, and evolve the data architecture powering leaderboards, evals, and scoring pipelines. Work closely with infrastructure engineers, researchers, and product leadership on application-layer systems customers touch directly.

Location: San Francisco

Workplace: Hybrid

Employment Type: Full time

Job Function: Software Engineering

Key Responsibilities

•Design and ship low-latency, high-reliability APIs and services powering leaderboards, evals, and Arena data products.
•Partner with the research team to turn evaluation methods into durable product features, including scoring pipelines, data models, and APIs.
•Build enterprise-grade backend capabilities such as usage metering, cost attribution, billing integration, authentication, RBAC, multi-tenancy, and audit logging.
•Unify public and private evaluation data by owning the data architecture, including schemas and making data queryable, consistent, and fast.
•Contribute to backend work across the stack for leaderboards and evals when needed to unify data architectures.

Pay and Benefits

Perks:Health InsuranceDentalVisionEquity

Key Requirements

•5+ years of backend engineering experience building product-facing APIs, services, and data systems at scale.
•Strong proficiency in a modern backend language, with Go preferred, and the ability to design APIs for long-term maintainability.
•Solid data fundamentals, including modeling, querying, and scaling Postgres, plus knowing when to use Redis, queues, or warehouses.
•Experience composing services into products, including integrating payments, auth, analytics, and/or data pipelines.
•A product-oriented mindset focused on developer experience, plus comfort with ambiguity in a fast-moving startup.

Experience:5+ yearsAIEnterprise SaaSDeveloper platforms

Skills:Product-mindedJudgmentCraftsmanshipCuriosityComfort with ambiguity

Tech Stack:GoPostgresRedisStripeOpenAIAnthropicVLLMLiteLLMLangChainMetronomeOrbQueue

Company Brief

Arena

LMArena operates a community-driven platform for evaluating and benchmarking large language models via crowdsourced pairwise comparisons and leaderboards, used by researchers and AI labs to measure real-world model performance. ([linkedin.com](https://www.linkedin.com/company/lmarena?utm_source=openai))

Industry: Developer Tools

Company Size: Small (11 to 50 employees)

Growth: Scaleup

Valuation: Unicorn (USD 1B+)

Funding: Series A

Headquarters: San Francisco, United States

Founded: 2025

Website LinkedIn

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Arena

2 weeks ago

Backend Engineer

✓ Verified Job

Canonical indexed version, validated from employer's careers page.

Source: Company careers pageValidated by: Fursa AI

Last checked: 16 hours agoStatus: Live

Job Summary

Location: San Francisco

Workplace: Hybrid

Employment Type: Full time

Job Function: Software Engineering

Key Responsibilities

•Design and ship low-latency, high-reliability APIs and services powering leaderboards, evals, and Arena data products.
•Partner with the research team to turn evaluation methods into durable product features, including scoring pipelines, data models, and APIs.
•Build enterprise-grade backend capabilities such as usage metering, cost attribution, billing integration, authentication, RBAC, multi-tenancy, and audit logging.
•Unify public and private evaluation data by owning the data architecture, including schemas and making data queryable, consistent, and fast.
•Contribute to backend work across the stack for leaderboards and evals when needed to unify data architectures.

Pay and Benefits

Perks:Health InsuranceDentalVisionEquity

Key Requirements

•5+ years of backend engineering experience building product-facing APIs, services, and data systems at scale.
•Strong proficiency in a modern backend language, with Go preferred, and the ability to design APIs for long-term maintainability.
•Solid data fundamentals, including modeling, querying, and scaling Postgres, plus knowing when to use Redis, queues, or warehouses.
•Experience composing services into products, including integrating payments, auth, analytics, and/or data pipelines.
•A product-oriented mindset focused on developer experience, plus comfort with ambiguity in a fast-moving startup.

Experience:5+ yearsAIEnterprise SaaSDeveloper platforms

Skills:Product-mindedJudgmentCraftsmanshipCuriosityComfort with ambiguity

Tech Stack:GoPostgresRedisStripeOpenAIAnthropicVLLMLiteLLMLangChainMetronomeOrbQueue

Company Brief

Arena

Industry: Developer Tools

Company Size: Small (11 to 50 employees)

Growth: Scaleup

Valuation: Unicorn (USD 1B+)

Funding: Series A

Headquarters: San Francisco, United States

Founded: 2025

Website LinkedIn