Senior Software Engineer, ML Infrastructure

LM Arena; San Francisco (CA); Hybrid; USD 200,000 - 300,000; Full time

Job summary

LM Arena is seeking a Senior Software Engineer specializing in ML infrastructure to lead the design of scalable systems that process real-time data requests. The role entails collaboration with researchers to enhance AI model evaluation, mentoring engineers, and ensuring system reliability, all within a dynamic environment.

Benefits

Competitive salary and meaningful equity

Comprehensive healthcare coverage (medical, dental, vision)

Opportunity to work on cutting-edge AI

Qualifications

• 5+ years of experience in software engineering with focus on infrastructure or large-scale data and ML systems.
• Deep expertise in distributed systems and stream processing.

Responsibilities

• Architect and scale high-performance, real-time API and data systems.
• Design and implement low-latency pipelines to process large-scale event streams.
• Collaborate cross-functionally with AI researchers and product leaders.

Skills

Distributed systems

Stream processing

Scalable backend architecture

Performance tuning

Fault-tolerant systems

Job description

Senior Software Engineer, ML Infrastructure

Location: SF Bay Area/Remote

Type: Full-Time

About the Role:

LMArena is seeking a Senior Software Engineer (Infrastructure) to lead the design and development of scalable, high-performance real-time data and API infrastructure. In this role, you’ll architect systems that capture and process large volumes of serving requests in real time, powering the insights that help researchers and developers build the world’s most advanced AI and its applications. Your work will be foundational to how we surface trustworthy, transparent, and timely evaluation signals across the platform. This role is ideal for someone who thrives in fast-moving environments, cares deeply about performance and reliability, and wants to build systems that help the AI community better understand what models are the best for their real-world use cases.

Responsibilities:

• Architect and scale high-performance, real-time API and data systems

• Design and implement low-latency pipelines to process and analyze large-scale event streams

• Ensure reliability through robust data integrity, availability, and consistency mechanisms

• Mentor and guide engineers on infrastructure best practices, architecture, and performance tuning

• Collaborate cross-functionally with AI researchers, product leaders, and engineers to anticipate evolving infrastructure needs and deliver resilient, extensible systems

Who is LMArena?

Created by researchers from UC Berkeley’s SkyLab, LMArena is an open platform where everyone can easily access, explore and interact with the world’s leading AI models. By comparing them side by side and casting votes for the better response, the community helps shape a public leaderboard, making AI progress more transparent, and grounded in real-world usage.

Why Join Us?

Trusted by organizations like Google, OpenAI, Meta, xAI, and more, LMArena is rapidly becoming essential infrastructure for transparent, human-centered AI evaluation at scale. With over one million monthly users and growing developer adoption, our impact is helping guide the next generation of safe, aligned AI systems—grounded in open access and collective feedback.

Our work is regularly referenced by industry leaders pushing the frontier of safe and reliable AI. Sundar Pichai, Jeff Dean, Elon Musk, and Sam Altman.

• High Impact: Your work will be used daily by the world’s most advanced AI labs.

• Global Reach: Develop data infrastructure powering millions of real-world evaluations, influencing AI reliability across industries at the top-tier

• Exceptional Team: We are a small team of top talent from Google, DeepMind, Discord, Vercel, UC Berkeley, and Stanford.

Requirements:

• 5+ years of experience in software engineering, with a focus on infrastructure or large-scale data and ML systems

• Deep expertise in distributed systems, stream processing, and scalable backend architecture

• Proven ability to design and operate low-latency, high-throughput, and fault-tolerant systems

• Strong foundation in systems design, performance tuning, and building reliable, fault-tolerant services

• Comfortable in a dynamic, high-ownership, fast-growth environment

What we offer:

• The cash compensation for this position in the market is $200K-$300K.

• Actual compensation will depend on job-related knowledge, skills, experience, and candidate location.

• Competitive salary and meaningful equity

• Comprehensive healthcare coverage (medical, dental, vision)

• 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.