Senior Software Engineer, Security Platform

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

About Sezzle:

With a mission to financially empower the next generation, Sezzle is revolutionizing the shopping experience beyond payments, blending cutting-edge tech with seamless, interest-free installment plans that make shopping smarter and more accessible. We’re not just transforming payments; we’re redefining how people discover, interact with, and purchase the things they love while driving real impact on merchant sales through increased conversions and higher order values.

As we continue to shape the future of fintech and retail, we’re building an innovative, dynamic team passionate about creating more than just a transaction but a truly unique shopping journey. If you’re excited about pushing boundaries in tech and delivering a game-changing experience for consumers and merchants alike, come join us at Sezzle and help create the future of shopping!

About the Role:

We are seeking a hands-on Senior Software Engineer, Security Platform, to build and own the platform the security team runs on: the services that discover, scan, triage and route security findings, the event-driven bus that connects them, and the CI security gates every team's pipeline runs through.

This is a development role on the security team, not a security-analyst role. Most of your time goes into designing, building and operating services in Go and Python on Kubernetes: new services where the programme needs them, the existing fleet where it has grown faster than its upkeep, and the NATS-based event platform that moves findings, inventory changes and notifications between them.

The security gates in our GitLab CI (SAST, SCA, secret detection, container and IaC scanning) and the agentic triage and review workflows are part of that platform, not the whole of it. Your job is to make these systems fast, low-noise, and reliable enough to be trusted by default without slowing delivery.

You will report to the Director of Information Security and work alongside the engineers who own detection and response and network and zero trust — your platform is what their work composes with.

At Sezzle, AI-assisted engineering is a standard part of how we build. In this role you will build reusable agentic workflows (Claude Code skills, CI review agents, automated triage and verification) that multiply what the team can cover, and hold that review discipline in the platform code you own.

What You’ll Do:

• Design, build, and operate security engineering services primarily in Golang and Python, on AWS and Kubernetes: new services where the programme needs them, and the upkeep, hardening and retirement of the existing ones.
• Own the event-driven platform between the security services: the NATS bus, its contracts and consumers, delivery guarantees and observability — so a finding, an inventory change or an alert reaches every service that acts on it.
• Integrate the platform end-to-end: scanners → finding system-of-record → tickets → metrics, so remediation state is visible and exam evidence is a by-product of engineering.
• Own delivery of the security gates — SAST, SCA, secret detection, container and IaC scanning: scanner selection and tuning, suppression workflow mechanics, false-positive burn-down, and the rollout tooling that takes a gate from advisory reporting to enforcing without blocking delivery.
• Build agentic security workflows: CI review agents, automated finding triage and verification, remediation helpers — tooling other engineers actually adopt.
• Build the triage-to-remediation automation: validate true positives by hand enough to prove the tooling right, then automate the loop — reproduction context, fix guidance, and routing to the owning teams and to vulnerability-management operations.