Casca - Senior Security Engineer

deCircle • San Francisco, CA

27d • $190,000 - $250,000 • Onsite

About The Position

We are looking for a Founding Security Lead with 4-8 years of experience to own and evolve the application security program at a fast-growing AI-native fintech startup. You'll be a "super IC" – someone who thrives doing hands-on security work while naturally growing into technical leadership. This role is ideal for someone with a strong application security background who is passionate about securing AI agents and agentic workflows in a highly regulated banking environment. You'll join an existing security foundation and take it to the next level as the company scales from Series A through its next phase of growth.

Requirements

• 4-8 years of experience as an application security engineer dealing with rapid growth
• Strong application security background; passion for securing AI agents and agentic workflows
• TypeScript
• JavaScript
• AWS
• GCP
• DevSecOps
• Secure SDLC
• Threat Modeling
• Application Security
• IAM
• SOC 2
• ISO 27001
• AI/LLM Security

Responsibilities

• Owning and maturing the application security program – building security tooling, processes, and secure SDLC practices that integrate naturally into how engineers ship code
• Securing the AI agent execution surface – partnering with engineering to establish robust security architecture for agentic workflows, ensuring data privacy and mitigating AI-specific vulnerabilities
• Driving automation of security processes – building detection pipelines, automating vulnerability management, and reducing manual security overhead
• Leading incident response – acting as primary incident commander and turning every event into systemic improvements
• Supporting compliance and customer trust initiatives – contributing to SOC 2, ISO 27001, and bank-driven security requirements

What This Job Offers

• Job Type: Full-time
• Career Level: Senior
• Education Level: No Education Listed