Staff AI Application Security Engineer

Relevance AI; United States; Hybrid; USD 127,000 - 169,000; Full time

Benefits offered by this job

ESOP – Employee Stock Ownership Plan

AI Productivity Benefit – Get up to $1

Parental Leave – 12 weeks

Milestone Merch

Food, Drinks & Community

Quarterly Team Events

Social Clubs

Sonder EAP

Job summary

Relevance AI in Sydney, Australia, is seeking a Staff Application Security Engineer to own security for a platform of autonomous agents that plan, decide, and act for enterprise customers. This hands-on IC role reports to the Head of Engineering and involves protecting APIs, data, and the model ecosystem.

You'll migrate access controls, secure authn/authz, and design guardrails, sandboxing, and prompt-injection defenses, with the potential to evolve toward an autonomous security team.

Qualifications

• Hands-on security expert for production platforms and APIs.
• Experience securing AI-native software and agent-based systems.
• Ability to design end-to-end security for autonomous agents.

Responsibilities

• Migrate access control to the new model and close gaps.
• Secure product surface: authn/authz, API security, input/output handling.
• Build guardrails for agent safety: permissions, sandboxing, prompt-injection defense.
• Establish least-privilege access across production environments.
• Support autonomous security capabilities and ongoing remediation.

Skills

Agentic security

AppSec depth

Hands-on ownership

Systems thinking

TypeScript

AWS

AI engineering basics

Tools

React

Node.js

Express.js

PostgreSQL

MongoDB

Kubernetes

Terraform

Dapr

Claude Code

Job description

Location Sydney, AU, Hybrid (3 days in office required)

About Us

At Relevance AI, we're building the home of the AI workforce. Our mission is simple: empower every team to delegate meaningful work to AI agents that think, act, and collaborate like experts.

With Relevance AI, anyone can create and manage intelligent agents that handle workflows, decisions, and collaboration - all within one unified platform. Our technology already powers industry leaders such as Canva, Databricks, Confluent, Autodesk, Lightspeed and Rakuten, helping them scale excellence across operations, marketing, and sales.

We're backed by Bessemer Venture Partners and raised our Series B in April 2025 to accelerate growth and push the boundaries of agentic automation. Headquartered in San Francisco and Sydney, we operate on a hybrid model and thrive on curiosity, collaboration, and execution - we move fast, think big, and win together.

If you want to define how the world works with AI, join us.

The Role

Our engineering team works at the frontier of AI-native software development - where curiosity, product thinking, rapid experimentation, taste and judgement are embedded in our ways of working.

As our Staff Application Security Engineer, you'll be the specialist behind application and product security for a platform of autonomous agents that plan, decide and act on behalf of enterprise customers.

This is a new threat surface. The established AppSec playbook still applies to our product, our APIs and our production environment - but stops well short of the harder questions. How do you let an agent act on real work without it going off the rails? How do you contain prompt injection when a model can't reliably tell instructions from data?

Enterprises won't hand real work to agents they can't trust. That makes security a reason customers choose our product, and we invest in it accordingly.

This is a specialist IC seat reporting to our Head of Engineering. No direct reports, and no handing a list of vulnerabilities to other engineers to fix.

We'll sponsor relocation to Sydney, and would like to hear from you if you're in the UK or Europe and looking to move.

How We Build

• AI engineering (coding agents, loops, eval) is core to every engineer's workflow.

• Engineers own product areas and customer problems end-to-end.

• We prototype quickly, validate with customers, and ship continuously.

• We care about product impact as much as technical quality.

Your Impact

• Migrate access control to our new model, and close any gaps.

• Secure the product surface: authn/authz, API security, input and output handling, supply-chain risk.

• Build the guardrails that let agents act safely: permissions, attribution, sandboxing, tool-use limits, prompt-injection defence.

• Establish least-privilege access across production, and make the secure path the fast path.

• Longer term, take us towards an autonomous security team: agents that continuously scan the platform and the code we ship, and help remediate what they find.

Who We're Looking For

While depth of experience is important, how you think matters more. In priority order:

• A view on agentic security. You've thought about what security means when agents do the work, not humans.

• AppSec depth on a production platform: authn/authz, API security, secure design and review, supply-chain risk. This is the core skill set we are hiring you for.

• Hands-on ownership. You'd rather fix it than report it.

• Systems thinking. You can talk through how an end-to-end autonomous system should be designed, and where it breaks.

• The basics for our stack: TypeScript, AWS, MCP, and AI engineering fundamentals - tool use, context, evals.

• Comfortable building with agents. It's how the whole team works. If you're not there yet you'll learn it here, but you need to want to.

This is a hands-on building role, and a deliberately specialist one. If you want to make security a product strength, build quickly, and stay close to the code, you'll enjoy it here.

Our Tech Stack (so far)

TypeScript and AWS you'll use from day one. Beyond those, what matters is how fast you pick up a new stack.

• Frontend: React, Vue.js, Typescript

• Backend: Express.js, Node.js, Typescript, Python

• Database: PostgreSQL, MongoDB

• Cloud Infrastructure: AWS, Vercel, Terraform, Kubernetes

• Agents and tooling: MCP, Dapr

• AI Coding Tools: Claude Code, Cursor, Codex and more

Why Join Us?

• We've set high standards in a high-trust, low-ego environment, and we hire exceptional people to do the best work of their lives. In return: competitive salary, equity, and career-defining scope. As an early team member you'll shape our culture and ways of working, not inherit them.

• We’re guided by our six principles: eyes on the prize, work on the factory - not just in it, be truth-seeking, know your customer by name, let's find a way, and momentum matters.

Meet Some of The Team

• Paulwyn, Head of Engineering

• Peter, Engineering Manager

Benefits

• ESOP – Employee Stock Ownership Plan so you can grow with the company

• AI Productivity Benefit – Get up to $1200 USD/year to spend on AI tools that help you work smarter and grow your skills

• Parental Leave – We offer 12 weeks of paid parental leave for all eligible new parents, and an additional 6 weeks for the birthing parent

• Milestone Merch – Celebrate your work anniversaries with customised Relevance AI swag

• Food, Drinks & Community – Enjoy catered lunches every Tuesday, Thursday and Friday with your teammates, plus Uber Eats dinners if you end up working late. Stay energised with free breakfasts, healthy snacks, and a fully stocked fridge of drinks

• Quarterly Team Events – Build stronger connections through fun, meaningful team bonding experiences every quarter

• Social Clubs – Share your hobbies and interests by joining or starting a club with your teammates. From hiking and chess to board game nights and social committee activities—there's something for everyone!

• Sonder EAP – Access 24/7 mental health and wellbeing support through Sonder, our Employee Assistance Program. #LI-Hybrid