MTS - Engineering (Security)

Collinear AI, Inc.; California (MO); On-site; USD 190,000 - 230,000; Full time

Job summary

Collinear AI, Inc. is seeking a senior security engineer to own security across our infrastructure, products, and customer data. You will lead security across AWS, CI/CD, and Kubernetes, and drive threat detection, response, and SOC 2 readiness.

You’ll work with researchers and engineers to set security direction, implement new measures, and guide customers on risk and compliance. Strong hands-on cloud security and automation are essential.

Qualifications

• 8+ years of experience in security engineering, with production cloud security.
• Deep hands-on AWS security experience (IAM, CloudTrail, GuardDuty, KMS, VPC).
• Offensive security background (pentesting, red team, vuln research).
• Experience isolating untrusted workloads with containers/microVMs (gVisor, Firecracker, Kata).
• Production-grade Python coding and automation.
• Experience building security programs in a startup environment.
• Ability to articulate risk to engineers, leadership and customers' security teams.

Responsibilities

• Harden sandboxes for untrusted code in AI agent environments.
• Own AWS security design, IAM, least privilege, and short-lived credentials.
• Build detection and response across cloud/Kubernetes; tune alerts.
• Protect customer data from arrival to delivery, incl. access controls and PII removal at scale.
• Lead customer security reviews and SOC 2/compliance efforts.
• Secure software supply chain: dependencies, CI/CD, secrets, GitHub org.
• Set guardrails for engineers against production infrastructure risks.
• Test systems like an attacker and fix identified issues.

Skills

Security engineering

AWS security

Offensive security

Container isolation

Python automation

Startup security program

Risk communication

Tools

AWS

gVisor

Firecracker

Kata Containers

Python

GitHub

Job description

As a Member of Technical Staff - Engineering (Security), you will own security across Collinear's infrastructure, products, and customer data. We build RL environments and training data for frontier AI labs and large enterprises. They trust us with sensitive data and access to their systems, and many of our environments run AI agents that are being trained to find and exploit vulnerabilities.

This is a senior, hands-on role. You will work alongside our researchers and engineering team to set the direction for, and implement, new security measures.

What you'll do

• Harden the sandboxes where AI agents run untrusted code, including cyber tasks where agents are actively trying to break out
• Own AWS security, including IAM design, least-privilege access, network boundaries, and short-lived credentials in place of long-lived keys
• Build detection and response across our cloud and Kubernetes environments, and tune alerts so the team acts on them
• Protect customer data from the moment it arrives to the moment we deliver, including access controls, secure delivery, and PII removal at terabyte scale
• Lead customer security reviews and compliance work, from security questionnaires and supplier onboarding to SOC 2
• Secure our software supply chain, including dependencies, CI/CD, secrets, and our GitHub organization
• Set guardrails for engineers and coding agents that work directly against production infrastructure
• Test our systems the way an attacker would, and fix what you find

About you

• You have 8+ years of experience in security engineering, much of it securing cloud infrastructure in production
• You have deep hands-on experience with AWS security, including IAM, CloudTrail, GuardDuty, KMS, and VPC design
• You have an offensive security background, such as penetration testing, red teaming, or vulnerability research, and use it to decide what to defend first
• You have isolated untrusted workloads with containers or microVMs, using tools such as gVisor, Firecracker, or Kata Containers, and know where that isolation tends to fail
• You write production-quality code, ideally in Python, and prefer automation to manual process
• You have built or grown a security program at a startup, and know how to prioritize when you can't fix everything at once
• You explain risk clearly to engineers, leadership, and customers' security teams