Member of Technical Staff, AI Safety

Trajectory Labs; Berkeley (CA); Hybrid; USD 250,000 - 400,000; Full time

Benefits offered by this job

Health coverage

401(k)

Food: Catered meals and snacks

Relocation allowance

Job summary

Trajectory Labs seeks a Member of Technical Staff to build a software factory that produces safety data for training and evaluating AI models. You will work with technical leads to develop training-data pipelines, environments, and evaluations that improve model safety.

This role is at an early-stage startup where responsibilities grow quickly. You will own engineering tasks, write production code, test, and debug while collaborating with leads on customer relationships and architecture

Qualifications

• Impact-driven: you want to improve the safety of frontier AI systems.
• Agent-native engineering: you use coding agents and LLMs as core development tools.
• Strong software engineering: you can design, build, test, and debug substantial systems, including code produced by agents.
• Autonomy and judgment: you can break down an engineering task, make good trade-offs, and keep the work moving.

Responsibilities

• Build evaluations, RL environments, and training-data pipelines.
• Write production code, develop tests, debug failures and improve reliability.
• Develop reusable tools and infrastructure for faster, trustworthy projects.
• Collaborate with engineers and researchers on larger technical problems.

Skills

Impact-driven

Agent-native engineering

Strong software engineering

Autonomy and judgment

Early-stage startup drive

Job description

Overview

Trajectory Labs is hiring a Member of Technical Staff to build a software factory that produces safety data to train, evaluate, and improve the world's most powerful AI models. You'll work alongside our technical leads to build training-data pipelines, environments, and evaluations that help make these models safer.

We're looking for an engineer who uses coding agents extensively and wants to grow through hands-on technical work: building, testing, and debugging systems. Technical leads guide project direction and lead customer relationships, while you take increasing ownership of the engineering work.

This is an early-stage startup role, so you should expect and enjoy being in a role where responsibilities can grow and priorities can quickly change.

About us

Safety data needs to keep pace with capabilities. As AI advances, we build evaluations that measure consequential agent failures and produce training data that helps mitigate them.

Although we're only a year old, we've already been featured in Anthropic's Fable 5 & Mythos 5 System Card, led Anthropic's prompt injection evaluation of Auto mode, and been featured in Meta's Muse Spark Safety & Preparedness Report.

Our areas of focus include red teaming, control, anti-distillation, AI safety reasoning, reward-hacking propensity evaluations, and embedded assessments.

A lot of companies say they use AI extensively. We mean it. PR count isn't the goal, but to give a concrete example, last week a single engineer merged 1,000 PRs.

About the role

You'll work with our technical leads on difficult safety and alignment problems, building evaluations, RL environments, and training-data pipelines. You'll write production code, develop tests, debug failures, and improve reliability, with support on architecture and project scoping.

You'll also help build our software factory: reusable tools and infrastructure, agent workflows, and automated tests that make each new project faster to build and easier to trust.

You'll collaborate with our engineers and researchers, taking on larger technical problems as your experience grows. The aim is to give labs dependable data and tools to train safer models, measure their behavior, and make better-informed decisions about how they are built and used.

What we're looking for

Essential

• Impact-driven: you want to improve the safety of frontier AI systems.

• Agent-native engineering: you use coding agents and LLMs as core development tools.

• Strong software engineering: you can design, build, test, and debug substantial systems, including code produced by agents.

• Autonomy and judgment: you can break down an engineering task, make good trade-offs, and keep the work moving, asking for guidance when you need it.

• Early-stage startup drive: you enjoy a fast pace, shifting priorities, limited structure, and taking on whatever is most important to help the company succeed.

Desirable

• Experience working in an AI safety or alignment context

• Experience building evals, red-teaming systems, RL environments, or model-training data

• Experience collaborating with frontier labs or other demanding technical customers

These criteria are a guide, not a checklist. If you want to do your life's work making frontier models safer and this role excites you, we encourage you to apply.

Logistics

Total compensation: Includes base salary, bonus, and the estimated annualized value of equity. Your level depends on the scope, autonomy, and impact we expect you to have:

• L4: $350,000

• L5: $520,000

• L6: $670,000

• L7: $900,000

Base salary: $250,000–$400,000 per year.

Location and workspace: Our team works out of Constellation in Berkeley, CA, and we prefer someone who can work alongside us there. We are open to remote for the right candidate.

Benefits:

• Health coverage: You'll receive a generous monthly pre-tax allowance to choose the medical, dental, and vision coverage that best fits your needs.

• 401(k): We offer a 401(k) retirement plan with a company match.

• Food: Catered lunch and dinner, unlimited snacks and drinks.

• Relocation: A generous moving allowance to relocate to Berkeley.

Visa sponsorship: We sponsor visas, although we cannot successfully sponsor every visa for every role or candidate. If we make you an offer, we will make every reasonable effort to secure the visa you need, with support from an immigration lawyer we retain to guide and coordinate the process.

Reports to: Ben West, CTO.