Full-Time

Member of Technical Staff

Mechanistic Interpretability

Vmax

Vmax

11-50 employees

Automates generation of reinforcement learning environments

Compensation Overview

$300k - $500k/yr

San Francisco, CA, USA

In Person

San Francisco office; hybrid work possible for exceptional candidates.

PhD

Category
AI & Machine Learning (1)
Required Skills
LLM
Python
PyTorch
Machine Learning
Reinforcement Learning

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Requirements
  • PhD or equivalent experience in machine learning, reinforcement learning, or a closely related field.
  • Track record of research excellence, as demonstrated by publications, open source work, deployed AI systems, or other substantial technical contributions.
  • Deep understanding of modern machine learning, especially reinforcement learning, representation learning, and large language models.
  • Strong familiarity with LLM post-training methods
  • Experience designing and running rigorous ML experiments, including ablations, baselines, evaluation design, and failure analysis.
  • Expertise with Python and at least one major ML framework such as PyTorch or JAX.
  • Ability to work independently on open-ended research problems and turn ambiguous ideas into concrete experimental programs.
Responsibilities
  • Develop methods for using mechanistic interpretability to extract useful training signals from the internal states of language models.
  • Turn representations, features, circuits, and causal model behaviors into intrinsic rewards for reinforcement learning.
  • Compare interpretability-derived rewards against human feedback, learned reward models, verifiers, and task-level outcome rewards.
  • Design metrics and baselines for reward quality, including alignment with intended behavior, generalization across tasks, robustness, and resistance to reward hacking.
  • Investigate how internal representations evolve during RL and post-training, and use these insights to improve training objectives.
  • Develop infrastructure for reproducible, large-scale experiments on LLM agents, interpretability tools, and RL environments.
  • Define and pursue a high-impact research agenda that advances Vmax’s goal of open-ended learning beyond imitation of human expertise.
Desired Qualifications
  • Experience with mechanistic interpretability techniques such as activation patching, probing, sparse autoencoders, feature attribution
  • Experience training or evaluating language-model agents in interactive, tool-using, or multi-step reasoning settings.
  • Familiarity with scalable RL infrastructure, distributed training, experiment tracking, and large-scale evaluation pipelines.
  • Experience developing reward models, verifiers, process supervision methods, or automated evaluation systems.
  • Demonstrated software engineering ability, especially in research codebases that require reliability, reproducibility, and iteration speed.
  • Ability to present technical results and their strategic implications to both research and non-research audiences

Vmax.ai builds tools to automate reinforcement learning (RL) development. It creates scalable RL environments from proprietary data so engineers can train agents for long-horizon tasks without a lot of manual RL engineering. The core product concept is to automatically transform company data and evaluation metrics into reusable RL environments, enabling post-training of large language model–based agents for domain-specific use cases. The company distinguishes itself by combining automated environment design with data-driven RL environment generation, aiming to cut human intervention in RL workflows. The founding team’s deep RL background, stealth mode status, and backing from South Park Commons position it to pursue enterprise-grade RL automation and domain-specific AI through a platform that handles data-to-environment conversion and subsequent agent fine-tuning. Its goal is to scale RL development by reducing setup work and enabling long-horizon tasks across domains.

Company Size

11-50

Company Stage

N/A

Total Funding

N/A

Headquarters

San Francisco, California

Founded

2025

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Simplify Jobs

Simplify's Take

What believers are saying

  • South Park Commons still lists Vmax as active and hiring on 2026-08-05.
  • Vmax published unix-ctf and a June 2026 arXiv paper, showing real research output.
  • A June 2026 job post offered $300,000-$500,000, signaling conviction and investor-backed hiring capacity.

What critics are saying

  • Stealth cuts product transparency; buyers cannot verify traction, pricing, or deployment quality, August 2026.
  • The company still depends on sample-efficient policy-gradient research, exposing execution risk versus faster imitators, 2026-06-09.
  • If environment generation fails to outperform handcrafted data, Vmax becomes a niche research shop, threatening survival.

What makes Vmax unique

  • Vmax turns proprietary data into RL environments, not generic model fine-tuning, updated 2026-08-08.
  • Its Campaign self-play infrastructure targets long-horizon tasks, especially Unix competence and coding, by 2026-06-22.
  • Founders Matthew Sargent and Augustine Mavor-Parker bring PhDs and Redwood Research AI-safety experience, 2026.

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