Partner 34, Lead, Security Engineering

a16z•San Francisco, CA

1d•$295,000 - $347,000•Hybrid

About The Position

Andreessen Horowitz (a16z) is seeking a Security Engineering Lead to build and shape the firm's security engineering team. This is a hands-on role where you will be involved in AI security discussions, code reviews, architecture conversations, and critical build decisions. You will be responsible for application security, enterprise security, and cloud security across the firm. You will collaborate closely with the internal engineering organization (ASG) to ensure the security of all their deliverables, including the AI tooling that is essential to the firm's operations. The role reports to the Head of Cybersecurity and will work with the SecOps Lead, ASG, a16z's CTO, and IT to ensure security functions as a partner rather than a blocker. Venture capital firms are targets for sophisticated threats such as capital call wire fraud, social engineering, and vishing. Your work will be crucial in protecting the firm, its Limited Partners (LPs), and its portfolio companies. This position requires an in-office presence two days a week in the San Francisco, CA office.

Requirements

7+ years of security engineering experience or equivalent demonstrated impact, with depth in both AppSec and CloudSec.
Track record of leading cross-functional projects and managing senior stakeholders.
Experience leading or significantly contributing to small teams (3 to 5 people). Formal management experience preferred but not required.
Comfortable running code reviews, threat models, and architecture discussions yourself.
Strong working knowledge of modern cloud and SDLC tooling (Terraform, Kubernetes, GitHub Actions, SAST, SCA, secrets scanning).
Experience operating in environments where security enables the business rather than gates it.
AI security knowledge, including model risk, prompt injection, and agent governance.
Experience translating technical security concepts, decisions, and trade-offs into terms non-technical audiences across the firm can act on.
Low ego, high empathy, and the capacity to collaborate effectively with diverse teams.

Responsibilities

Own AppSec and CloudSec across AWS and GCP, including the roadmap, tooling stack, and engineering partnership.
Help secure a16z's AI work, including internal AI tooling, agent governance, model risk, and prompt injection defense.
Build a partnership with engineering where security is integrated early in the process, not as an afterthought.
Maintain a technical focus through code reviews, architecture discussions, threat models, and critical build decisions.
Run and support cross-functional initiatives involving both technical and non-technical teams across the firm, and manage the associated relationships.
Protect the firm, its LPs, and its portfolio companies from targeted, sophisticated threats.