Experteer Overview
In this role you help safeguard Factorial’s software by proactively finding and remediating vulnerabilities across apps, APIs, and AI features. You’ll work with Product and Engineering to embed secure practices, automate security checks, and build guardrails for developers. The position emphasizes practical security at speed, including AI security considerations and collaboration with bug bounty programs. You’ll contribute to scalable security tooling and stay ahead of threats in a fast-moving, AI-driven environment.

Compensaciones / Incentivos
• Perform proactive penetration testing across applications, APIs, infrastructure, and AI features
• Reproduce and validate external vulnerability reports from bug bounty programs
• Collaborate with development teams to remediate findings and improve secure coding practices
• Improve triage, validation, and remediation of vulnerabilities from various sources
• Hunt for recurring vulnerability patterns based on root cause analysis and past incidents
• Build security automations, agents, and CI/CD controls for early issue detection
• Secure Factorial’s use of AI, including LLMs, agents, data access, and tool permissions




• Contribute to security tooling, automations, and infrastructure
• Stay current with security research, threats, and AI security risks

Responsabilidades
• 3+ years of professional experience in Application Security, Offensive Security, or Penetration Testing
• Web Application Penetration Testing experience mandatory
• Degree in Engineering or Computer Science
• Strong knowledge of web apps, databases, network protocols, and operating systems
• Solid understanding of cybersecurity fundamentals, CVSS, testing methodologies, and tooling
• Scripting or programming skills used in security testing/automation (e.g., Python or Bash)
• Ability to reason across multiple security domains and learn quickly
• Willingness to learn about AI security topics (LLM testing, prompt injection, data exposure)
• English fluency

Requisitos principales
• ESOP plan
• private health insurance
• office-first with flexible remote work
• breakfast in the office and organic fruit
• language classes
• food discounts

📌 Offensive Security Engineer (Barcelona)
🏢 Factorial Hr
📍 Barcelona