Remote Senior Application Security Engineer

Bazeta; Northern (KY); Remote; USD 140,000 - 180,000; Full time

Benefits offered by this job

Medical, dental, and vision coverage

Equity (ISOs)

401(k) program

Parental leave

Wellness memberships

Unlimited PTO and holidays

Flexible work environment

Lunch reimbursement

Employee Resource Groups

Learning and Development stipend

Transparent culture

Job summary

Upside is seeking a Staff Application Security Engineer to own the application security program across mobile, web, and cloud systems. You will report to the Product Security Manager and collaborate with Cloud Security and Engineering to scale secure software delivery, build guardrails, and provide practical security guidance to engineers.

You will triage findings from scanners, code reviews, and annual pen tests, drive remediation with cross-functional teams, and design threat models for

Qualifications

• 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, everyday use of AI in your security work; this is about how you already work, not a tool you've tried once.
• Working knowledge of our stack: AWS security (Lambda, API Gateway, IAM least privilege, secrets handling) and CI/CD security in GitHub Actions, depth in the underlying mechanics matters more here than years in any one platform.

Responsibilities

• 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.

Skills

Python code review

Threat modeling

Security improvements

AI in security

Security ownership

CI/CD security

Tools

GitHub Actions

Terraform

AWS Lambda

API Gateway

DynamoDB

S3

Job description

Upside is seeking a Staff Application Security Engineer to own the application security program across mobile, web, and cloud systems. You will report to the Product Security Manager and collaborate with Cloud Security and Engineering to scale secure software delivery, build guardrails, and provide practical security guidance to engineers.

You will triage findings from scanners, code reviews, and annual pen tests, drive remediation with cross-functional teams, and design threat models for