Senior Software Engineer, Security Platform

About the role

Sezzle is looking for a hands‑on Senior Software Engineer to own and evolve its security platform. You will design, build, and operate services that discover, scan, triage and route security findings, as well as the event‑driven bus that connects them. This is a development role on the security team, not a security‑analyst position.

Key responsibilities

• Design, develop, and maintain security engineering services in Golang and Python on AWS and Kubernetes.
• Own the NATS‑based event platform, ensuring reliable delivery, observability and contract stability.
• Integrate scanners, finding system‑of‑record, ticketing and metrics to provide end‑to‑end remediation visibility.
• Deliver and tune CI security gates (SAST, SCA, secret detection, container and IaC scanning) in GitLab CI.
• Build AI‑assisted agentic workflows (Claude Code, CI review agents) to automate triage and verification.
• Participate in threat modeling, secure design reviews and on‑call rotation for owned services.

Required profile

• 6+ years of professional backend software engineering experience.
• Recent experience shipping production changes within the last 30 days.
• Strong proficiency in Golang and working knowledge of Python.
• Hands‑on experience with event‑driven systems (NATS, Kafka) and CI/CD pipeline tooling (GitLab CI).
• Practical web‑application security knowledge (OWASP Top 10) and experience with SAST/SCA tools.

Required skills

• Golang
• Python
• AWS
• Kubernetes
• NATS (or similar messaging systems)
• GitLab CI
• SAST tools (Semgrep, CodeQL)
• SCA tools (Snyk, Trivy, Grype)
• Secret‑scanning tools (gitleaks)
• AI‑assisted development tools (Claude Code, Codex)