Member of Technical Staff (Security Engineering)

The role

Aretta runs code and agents we didn’t write, for customers who trust us with their most sensitive systems: their source code, their infrastructure, and their bugs before anyone else knows about them. That trust has to be earned in how we build, not added afterwards. You’ll be our first security engineer: a builder who makes security part of every design decision, attacks our own systems before anyone else can, and sets the standard the rest of the team follows.

Problems you’d own

• Run untrusted code safely. Our platform executes customer code and autonomous agents for many customers at once. Design the isolation so no customer’s code, data or agents can ever reach another’s.

• Attack us first. Red-team our infrastructure, our product and our verification pipeline itself, and turn every finding into a fix for the whole class of problem.

• Secure the agents. Agents read untrusted input, call tools and touch real systems. Define their permissions, sandboxes and audit trails, and stay ahead of prompt injection and the attacks nobody has named yet.

• Make enterprise security easy to say yes to. Single sign-on, role-based access, audit logs and data handling that pass a large customer’s security review without a fight.

• Protect customer data. Decide how customer code and results are stored, encrypted, retained and deleted, and make privacy a property of the system rather than a policy document.

• Make security everyone’s habit. Run design and code reviews, set secure defaults, and help the team build safely without slowing down.

You don’t need to have done all of this. We care about how you’d approach it.

You might be a fit if

You’ve secured systems running in production, and you’ve found real vulnerabilities, ideally before anyone else did. When something breaks, you fix the root cause. You build security in from the start: when infrastructure is being planned, built or scaled, you’re part of the design early, so security is part of how the system works and not something added after it ships. You can talk through a threat model with an engineer on the team or with a customer’s security team, and you want the secure way to be the easy way for everyone else.

You don’t need

• A background in formal methods. You'll learn by working with us.

• A security certification.

• Experience leading a security team. You can grow into that here.

Where this can go

As we grow, this role can grow into Head of Security, and for someone who also wants the policy and leadership side, into CISO.

Bonus points

• Isolation: you’ve built sandboxing or isolation with containers, microVMs, gVisor or Firecracker.

• AI security: you’ve worked on the security of LLMs or agents.

• Offense and response: you’ve run a bug bounty, a red-team exercise or incident response.

Who we hire

We hire at every level, and we mean it. If you’re senior, you’ll come in as a hands-on engineer and grow into leading and building a team. If you’re early in your career, fresh out of school or a few years in, you’ll get real ownership fast and as much scope as you can take on. What matters is the same bar for everyone: mastery, the drive to grow, and the instinct to help others grow too.

Compensation and logistics

• Benefits: unlimited PTO, health, dental and vision insurance, and a 401(k).

How we work

We work in roughly six-week cycles: five intense weeks, then a week for reflection, polish, feedback and mentorship. We bring opinionated ideas backed by evidence, bias for action, fix the class of problem rather than the instance, and close the loop with the people we serve. Read more in Our Culture.

Aretta comes from aretē, the Greek word for excellence and virtue: becoming the best version of yourself in everything you do. We value excellence for its own sake, and we believe it’s built across a whole life, not just the hours at a desk.