Security Infrastructure Engineer

Sezzle is a fintech company that provides interest-free installment plans, revolutionizing the shopping experience. We are building an innovative team to shape the future of fintech and retail.

We are seeking a hands-on, high-impact Senior Security Infrastructure Engineer to strengthen our security posture across cloud infrastructure, applications, and developer workflows. You will have a high degree of ownership and autonomy to identify risks, investigate issues, and drive meaningful security improvements. You will work across vulnerability management, detection engineering, supply chain security, and incident response.

• Lead and operate vulnerability management across infrastructure, platforms, and applications, including internal scans, dependency analysis, and external findings.
• Build, operate, and mature SIEM/XDR capabilities, including log ingestion, detection rule development, alert tuning, and investigation workflows.
• Investigate and respond to security incidents across cloud infrastructure and applications, performing root cause analysis and driving long-term fixes.
• Design and implement detection strategies for suspicious activity, including data exfiltration patterns.
• Lead and contribute to threat modeling exercises and security design reviews.
• Apply deep expertise in AWS and Kubernetes to design, secure, and improve resilient cloud infrastructure.
• Drive infrastructure and CI/CD hardening initiatives, focusing on reducing software and container supply chain risk.
• Lead efforts to implement and improve dependency and container supply chain risk detection systems.
• Partner with engineering teams to remediate vulnerabilities and improve secure development practices.
• Support and implement security controls aligned with PCI DSS, SOC 2, and other compliance requirements.
• Develop and implement automation (including AI) to improve efficiency in security operations.
• Triage and validate external security findings, distinguishing true positives and coordinating remediation.

• 6+ years of experience in security, software, or infrastructure engineering.
• Hands-on experience securing cloud-based production systems.
• Experience contributing to threat modeling and security design reviews.
• Strong hands-on experience in vulnerability management.
• Experience with SIEM platforms (e.g., Wazuh, Splunk, ELK).
• Practical experience triaging findings from vulnerability scanners and bug bounty programs.
• Strong knowledge of AWS, Linux, and Kubernetes infrastructure.
• Experience improving infrastructure security, including CI/CD hardening and mitigating supply chain risks.
• Experience with container and dependency security tools (e.g., Snyk, Trivy, Grype).
• Ability to investigate issues directly using logs, cloud tooling, and system-level data.

• Salary range: $5,000 - $9,500 per month (Gross in USD).
• Remote work from Brazil.