Security Engineer

The role

You will own the cloud and product security posture by working across AWS and Cloudflare. You will harden the secure SDLC, run pen testing, and threat-model product features.

What you will do

• Drive SAST, dependency scanning, secrets detection, and PR-blocking standards
• Harden AWS and Cloudflare estate including IAM, secrets, network segmentation, KMS, WAF, and GuardDuty
• Run end-to-end pen testing with AI-driven scanners and human researchers
• Threat-model product features like Auth providers, multi-tenant APIs, and agent tool-calling paths
• Build detection and response capability around credential and authentication flows
• Partner with engineering for architecture reviews and security in code review
• Use LLMs and agents to accelerate security workflows
• Support compliance work for SOC 2 and ISO 27001

Required qualifications

• 3+ years in security engineering with hands-on AWS security
• Strong coding ability in TypeScript or Python or Go
• Application security fluency including OWASP Top 10, threat modeling, and code-level reviews
• Experience securing a B2B SaaS multi-tenant production environment
• Comfort owning end-to-end work
• Clear communication with engineers, product, and non-technical stakeholders
• Bias toward automating security checks

Nice to have

• IaC fluency in AWS CDK or Terraform
• Experience with Aikido, Drata, Cloudflare Workers, or pen testing in a compliance-mature environment

Benefits

• Meaningful share options (EMI)
• Flexible hours and hybrid working
• 25 days holiday per year plus 1 additional day per year of tenure
• Private health insurance including dental and optical
• Up to 30 days per year working from abroad
• Optional co-working space paid for from remote setup allowance
• £15/day lunch budget when working from London office up to £180/month
• £1,000 remote setup allowance plus £500/year top-up
• Health, fitness and gift card discounts
• Cycle2Work and Electric Cars scheme
• Annual team offsites

About the company

StackOne is the integration infrastructure for AI agents. It is backed by GV and Workday Ventures.