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Summary

The Senior AI Security Engineer is the senior technical owner for the day-to-day security of OneStream’s internal AI environment. As the company expands its use of AI, this role drives the technical execution of the internal AI security strategy, ensuring internal AI platforms, connectors, agents, and workflows are deployed securely, and is accountable for the outcomes.

The Senior AI Security Engineer co-develops and executes the internal AI security roadmap with the AI Security Architect/Manager, architects and operates the company’s AI Detection and Response (AIDR) capability, sets the standard for security reviews of new and third-party AI tooling, and makes independent risk decisions on behalf of the Security team. The role also owns the metrics that measure internal AI security success, serves as the Security team’s AI automation champion, and acts as technical lead and mentor for additional AI Security team members as the function grows.

This is a senior, hands-on, high-autonomy role that reports to the AI Security Architect/Manager and partners with IT, Legal, Compliance, and business leaders to enable the organization to adopt AI securely.

Primary Duties and Responsibilities

Serve as the senior technical owner for the day-to-day security of OneStream’s internal AI environment, including enterprise AI assistant platforms, agents, connectors and tool integrations such as MCP, and AI-enabled business workflows, from intake through production; co-develop and execute the internal AI security roadmap with the AI Security Architect/Manager.
Define and own the security review standard for enterprise AI assistant and agent configurations, connectors, and workflows, including tenant-level controls, permissions, data-sharing and retention settings, integration configurations, and custom agents and skills; make independent approval decisions and set the secure-by-default baselines that internal AI builders follow.
Architect, implement, and own the AI Detection and Response (AIDR) capability end to end: monitor AI usage across the enterprise, detect prompt injection, tool abuse, data exfiltration, and anomalous agent behavior, and integrate alerting and response into Security Operations workflows.
Lead and set the standard for security reviews of new and third-party AI tooling, including AI-enabled SaaS features, connectors, MCP servers, and models, against OneStream security policies and procedures, and serve as the escalation point for complex or high-risk reviews.
Serve as the Security team’s AI automation champion: identify opportunities to incorporate AI into security operations, such as alert triage and enrichment, detection engineering, and vulnerability management, and lead the design and delivery of those workflows to multiply the team’s capacity.
Lead threat modeling of internal AI use cases against AI-specific attack classes, including prompt injection, jailbreaks, tool misuse, excessive agency, sensitive data leakage, and AI supply-chain risk, and influence architecture decisions across IT and Engineering.
Define, implement, and own the metrics program for internal AI security, and report AI security posture and program progress to Security leadership.
Operationalize AI governance by partnering with IT, Legal, Privacy, and business teams to translate AI acceptable use, data classification, and security policies into technical guardrails, secure-by-default patterns, review checklists, and training that enable employees and internal AI builders to adopt AI securely.