Staff Application Security Engineer

Meet Upside: We created Upside to transform brick-and-mortar commerce. Our technology uses the sophistication of online retail—profit measurement, attribution, and incrementality—to provide users with more value on their everyday purchases and brick-and-mortar businesses with new, profitable customers. We’ve helped millions of users earn 2 to 3 times more cashback than any other product, and hundreds of thousands of brick-and-mortar businesses earn measurable profit. Billions of dollars in commerce run through the Upside platform every year, and that value goes directly back to our retailer partners, the consumers they serve, and important sustainability initiatives. The Impact You'll Make You'll report to the Product Security Manager and work closely with our Cloud Security and Engineering teams to scale secure software delivery across Upside. This role owns our application security program, reducing real risk across mobile, web, and cloud systems by driving remediation, building engineering guardrards, and creating security guidance that developers actually use. You'll also work both sides of the AI problem: we use AI to do security work, and we secure the AI systems we're building. If you came into security from a product engineering background, we'd especially love to hear from you. Own Upside's application security program, the standards, the vulnerability management pipeline, and the guardrails that stop entire classes of defects from coming back Drive vulnerability management outcomes by triaging and tuning findings from scanning, code review, and our annual penetration test, then partnering with engineering teams to get fixes shipped and verified Lead application security reviews and threat models for high-impact work across mobile, web, and backend systems, and document risk decisions with clear mitigation plans Review and threat model agentic AI workflows, and define security controls for tool use, data access, and action execution Build and improve the automation that triages findings, prioritizes them with service context, and produces remediation guidance engineers can act on Build guardrails that scale beyond our team; repository baselines, required checks in GitHub, secure-by-default patterns for AWS workloads, reusable templates, and a security champions program What You'll Bring 6+ years in application or product security or equivalent depth in secure software engineering with meaningful application security ownership Strong Python code review skills, you can open a Lambda, understand what it does, and explain to the engineer who wrote it exactly what's wrong and why A track record of shipping security improvements that reduced real risk, not just running scanners or writing policy, you can point to fixes that landed, were verified, and to remediation you drove across teams you didn't own Experience with threat modeling and secure design review, engaging with designs before they ship, not only with code after the fact Practical,