OverviewIn this role you will lead penetration testing efforts for Klarna's internal and public systems, triage bug bounty submissions and external pentest findings, and propagate security insights across teams.
You'll analyze issues across the codebase and infrastructure, build tooling, and mentor engineers and SOC colleagues.
The position sits on the Offensive Security team and centers on maturing Klarna's security program.
This is a hands-on, impact-driven opportunity in a fast-moving fintech environment.
ResponsabilitàRun white-box and black-box penetration tests on internal and public-facing systems
Manage triage and investigation of Bug Bounty submissions and external pentest findings
Perform variant analysis to identify related issues across the codebase and infrastructure
Assess security of third-party solutions and integrations
Build tooling for reconnaissance, automation, and metrics collection
Guide developers, product security teams, and SOC investigations with practical recommendations
Lead demos,



workshops, and training to spread offensive security practices
Assess overall security of Klarna's tech stack and contribute to maturing the security program
Requisiti fondamentali5+ years of conducting penetration tests and security assessments on production systems
Ability to read code and identify vulnerabilities in Java and Node.js
Experience with AWS and microservice architectures
Clear, remediation-focused writing that translates findings into actionable steps
Python scripting to develop own tooling
Proactive, self-driven approach to advancing offensive security within the organization
Clear written and verbal communication
Initiative and self-motivation
Collaboration across cross-functional teams
Penetration testing and security assessments
Java and Node.js code review
AWS cloud security and microservices

📌 Senior Offensive Security Engineer (Bardi)
🏢 Klarna
📍 Bardi