Security Engineer

Founded in Australia in 2019, our mission is to create the most efficient AI infrastructure by combining cutting-edge technology with a steadfast commitment to sustainability.

At Firmus, we are unique in our approach. We design, build, and operate a new class of digital infrastructure – the AI Factory. Through our model-to-grid technology approach, we have pushed the boundaries of multi-generational liquid cooling systems, energy management, AI software orchestration, and construction. Fo...

Our large-scale GPU cloud platform, Firmus AI Cloud, is purpose-built to deliver energy-efficient AI compute at scale to customers.

Own the CI/CD security gates that every production repository passes through: SAST, DAST, SCA, secrets detection, and SBOM generation. 
Build the systems that do the repeatable work: finding triage, dependency uplift, evidence collection, and draft threat models.  
Ship the secure paved roads other teams build on: reusable libraries, service templates, and developer tooling. 
Write and review code in the services you protect, including the security-critical paths that tools miss. 
Set the application security standard and control for authentication, authorisation between services, tenant isolation at the application boundary, secret handling and logging. 
Lead threat modelling and secure design review. Define what an attacker can do and what must be true before it ships. 
Set the security requirements for the AI assistants and agents we ship e.g. prompt injection, context poisoning. 
Govern which tools and tool servers our AI agents and software engineers may reach, and how those integrations are scoped, allow-listed, and audited. 
Own application security posture across our services: what is covered, what is open, what is accepted with a named owner and an expiry, and what is overdue. 
Prioritise fixes on exploitability and exposure alongside CVSS and hold them to the Firmus vulnerability SLAs. 
Drive remediation with the teams that own the code so issues close at the source. 
Extend SOC 2 Type 2 and ISO 27001 into the software delivery path as services and sites grow. Evidence that a control ran should be a query, not a spreadsheet exercise. 
Coach security champions inside each team so secure design decisions get made without waiting for you. 
Provide application-security expertise during incidents and convert recurring failure modes into gates, tests, standards, or developer tooling. 
Give engineering leadership a straight read on application risk and release readiness. Join customer conversations when the question is application security. 

Bachelor's degree in computer science or a related technical field. 
7+ years in application security, product security, or software engineering with a security focus. 
Experience securing a public cloud or multi-tenant platform with a public API. 
Deep, practical knowledge of the OWASP Top 10 and the OWASP API Security Top 10. Has threat modelled multi-tenant APIs in production: identity, authorisation between services, tenant isolation, and the ways a client abuses a published contract using STRIDE or an equivalent method, both for REST and gRPC. 
Has improved the security posture of software built by other engineering teams through standards, tooling, review, or secure-by-default patterns. 
Has owned CI/CD security gates in production (SAST, DAST, SCA, secrets detection, SBOM) and tuned them to deliver actionable findings with low false-positive rates that engineers trusted and acted upon. 
Writes production-quality code in at least one of Python, Go, or TypeScript. 
Has replaced manual security work with automation: finding triage, dependency uplift, evidence collection, or regression tests that run without someone watching them. 
Hands-on with LLM-backed or agentic features: prompt injection, tool misuse, agent identity and delegated credentials, cross-tenant data leakage, and controls on generated code reaching production. Familiar with OWASP guidance for LLM and agentic applications. 
Deep practical experience with OAuth, OIDC, JWT, RBAC or ABAC, application-layer cryptography, token handling, and secrets in software. 
Has worked under SOC 2 Type 2 or ISO 27001 and can produce evidence that a control ran. 
Willing to join incident response for application and API security. 
Willing to travel overseas occasionally when the role requires it. 
Clear and effective written and verbal communication in English 
Experience securing AI agents, sandboxed code execution environments, or systems where AI-generated output can trigger automated actions. 
Has run a vulnerability disclosure programme. 
Security certifications with application-security depth, such as CSSLP or OSWE.