~2mo ago

Judgment Labs — Full-Stack Engineer

EngineeringFullstack Developer

4 views0 saves0 applied

Quick Summary

Key Responsibilities

simulated environments for stateful evals, trajectory replay, and monitors for unintended behavior. Make long, multi-step reasoning trajectories understandable in minutes.

Technical Tools

EngineeringFullstack Developer

Responsibilities

~1 min read

→Build interfaces that make large-scale, parallel agent investigations legible — turning thousands of production traces and a wide range of failure signals into a single actionable answer.
→Build the platform for verifying agent changes: simulated environments for stateful evals, trajectory replay, and monitors for unintended behavior.
→Make long, multi-step reasoning trajectories understandable in minutes.
→Own the improvement loop end to end, turning production data into datasets, judges, and regression checks.
→Build and maintain the SDK and a terminal-first developer experience.
→Own core platform infrastructure: workspaces, permissions, billing, usage, and limits.

Tech stack: Full-stack (data layer through UI), SDK development, terminal-first tooling, agent/LLM infrastructure.

Requirements

~1 min read

3–7 years of full-stack engineering experience, comfortable owning systems from the data layer through the UI
Hands-on experience building with LLMs or AI agents (or a clear, demonstrated drive to ramp fast)
A track record of shipping and scaling production systems end to end
Comfortable working directly with customers to understand needs and solve real problems (~30% of the role)
Strong problem-solving in fast-moving, ambiguous environments
Clear, direct, persuasive communication across technical and non-technical audiences
Based in San Francisco or open to relocating; in-office 5 days a week

Nice to Have

~1 min read

Prior work on evals, observability, or agent behavior-monitoring products
Strong engineering pedigree from a respected product company; top-tier infrastructure experience is a bonus
Prior forward-deployed or solutions engineering experience
Early-stage / 0-to-1 startup experience as an early hire
A technical edge beyond delivery — coding competitions, research, or similar
Founder background or a clear founder-to-be trajectory
Full-stack comfort with real backend and infrastructure depth

What We Offer

~1 min read

✓Own a real product surface end to end — from customer conversations to shipped features.

✓Join a small, high-velocity, well-backed team working at the frontier of AI agent reliability.

✓Competitive compensation up to $300K + equity, with a strong benefits and perks package.

Location — San Francisco, CA
Work policy — On-site, 5 days/week; relocation supported
Compensation — $200,000–$300,000 + equity
Visa sponsorship — Considered case-by-case for exceptional candidates; primary scope is candidates who don't require sponsorship
Employment type — Full-time