Jobs

Member of Security Staff

Parameter · San Francisco, CA, US · Y Combinator Winter 2026

Salary
$130K - $180K
Location
San Francisco, CA, US
Type
Full-time
Experience
Any (new grads ok)
Visa
US citizen/visa only
Posted
31 Mar 2026
Listed until
23 Nov 2026, or when it closes

Apply on Work at a Startup ↗

About the role

We're looking for an Offensive Security Engineer who can bridge the gap between manual penetration testing and our autonomous AI agents. You'll conduct hands-on security assessments across web applications, APIs, and cloud infrastructure while also working to improve the agents that scale that work. You'll review and validate agent findings, develop custom exploits and tooling, and contribute directly to the platform as an engineer.

What you'll do:

Execute penetration tests across web applications, APIs, and cloud environments. Review, validate, and enhance findings generated by our autonomous agents. Develop custom exploits, tools, and methodologies for complex vulnerabilities. Contribute production code to improve agent capabilities and coverage. Produce actionable security assessment reports with clear remediation guidance. Work with customer engineering teams to walk through findings and fixes.

What we're looking for:

3+ years of professional penetration testing or offensive security experience with a track record of identifying critical vulnerabilities. Strong software engineering skills in Python and/or TypeScript. Deep understanding of web application security, including injection flaws, broken access control, authentication bypasses, and SSRF. Experience with common offensive tooling (Burp Suite, Nuclei, custom scripts) and comfort building your own. Familiarity with cloud security across at least one major provider (AWS, GCP, Azure).

Nice to have:

Experience with AI/LLM security, including prompt injection and agent manipulation. Bug bounty track record or published CVEs. Familiarity with OAuth/OIDC and SCIM attack surfaces. Relevant certifications (OSCP, OSWE, OSEP), though we care more about what you can do.

Apply on Work at a Startup ↗ Applications go to Parameter directly. CISO AI takes no fee and has no part in hiring.

CISO AI lists open roles at Y Combinator startups and at the portfolio companies of Australian venture funds, read daily from their own boards. This role is Parameter's own listing; it leaves this page the day it leaves their board.