Security Infrastructure Engineer

Sezzle is a fintech company revolutionizing the shopping experience with interest-free installment plans. We're building an innovative team to shape the future of fintech and retail.

• Lead and operate vulnerability management across infrastructure, platforms, and applications - including internal scans, dependency analysis, and external findings, validating true positives and driving remediation with engineering teams.
• 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 using application and database telemetry.
• Lead and contribute to threat modeling exercises and security design reviews to identify risks early and strengthen architecture.
• Apply deep expertise in AWS and Kubernetes to design, secure, and improve resilient and secure cloud infrastructure at scale.
• Drive infrastructure and CI/CD hardening initiatives, with a focus on reducing software and container supply chain risk.
• Lead efforts to implement and improve dependency and container supply chain risk detection systems and controls.
• Partner closely with engineering teams to remediate vulnerabilities and improve secure development and deployment practices.
• Support and implement security controls aligned with PCI DSS, SOC 2, and other compliance requirements.
• Develop and implement automation (including AI where appropriate) to improve efficiency in security operations, detection, and response.
• Triage and validate external security findings, distinguishing true positives and coordinating remediation.

• 6+ years of experience in security, software, or infrastructure engineering, with hands-on experience securing cloud-based production systems and working with real-world security challenges.
• Experience contributing to threat modeling and security design reviews for modern systems.
• Strong hands-on experience in vulnerability management, including scanning, triage, validation, remediation coordination, and verification.
• Experience working with SIEM platforms (e.g., Wazuh, Splunk, ELK) for detection engineering, monitoring, and incident response.
• Practical experience triaging findings from vulnerability scanners and bug bounty programs.
• Strong knowledge of AWS, Linux, and Kubernetes infrastructure, including security architecture, hardening, and operational best practices.
• Experience improving infrastructure security, including CI/CD hardening and mitigating software supply chain risks.
• Experience with container and dependency security tools (e.g., Snyk, Trivy, Grype, etc.).
• Ability to investigate issues directly using logs, cloud tooling, and system-level data.

• The salary range for this role is $5,000 - $9,500 per month (Gross in USD).