Security Engineer

StackOne

Security Engineer responsible for safeguarding AWS and product security at StackOne. Collaborating with engineering to enhance security within a SaaS integration platform.

Posted 5/20/2026full-timeLondon • 🇬🇧 United KingdomMid-LevelSeniorWebsite

Tech Stack

Tools & technologies

AWSGoPythonSDLCTerraformTypeScript

About the role

Key responsibilities & impact

Own the secure SDLC: drive SAST, dependency scanning, secrets detection, and PR-blocking standards across every repository.
Harden our AWS and Cloudflare estate: IAM, secrets, network segmentation, KMS, WAF, GuardDuty, and zero-trust patterns.
Run pen testing end-to-end: scope and coordinate engagements with both AI-driven scanners and human researchers, then drive findings through fix and retest.
Threat-model product features before they ship, new Auth provider, expanded multi-tenant APIs, connector executions, agent tool-calling paths etc.
Build detection and response capability around credential and authentication flows, with observability that closes incidents fast.
Partner with engineering to raise the bar day-to-day: architecture reviews, written standards, and security embedded in code review.
Use LLMs and agents to accelerate security workflows (triage, code review, evidence gathering) with guardrails you trust and help secure and monitor the (code/application/device) fleet.
Support compliance work where it intersects security engineering: SOC 2, ISO 27001, customer security reviews, and pen test responses.

Requirements

What you’ll need

3+ years in security engineering with hands-on AWS security: IAM, KMS, networking, secrets, GuardDuty / Security Hub.
Strong coding ability in TypeScript or Python or Go comfortable shipping production code, not just configs and scripts.
Application security fluency: OWASP Top 10, threat modeling, and code-level reviews on real systems.
Experience securing a B2B SaaS multi-tenant production environment.
Comfort owning end-to-end work: scope, ship, measure. You don’t wait for a queue.
Clear communication with engineers, product, and non-technical stakeholders.
Bias toward automating security checks instead of running manual checklists.
(Preferred) IaC fluency in **AWS CDK** or **Terraform** , comfortable reviewing infrastructure code for security misconfigs and writing custom scanning rules.
(Preferred) Experience with Aikido, Drata, Cloudflare Workers, or pen testing in a compliance-mature environment.

Benefits

Comp & perks

Meaningful share options (EMI) - share in the company’s success as we grow
25 days holiday + 1 additional day per year of tenure
Private health insurance - including dental & optical
£15/day lunch budget when working from our London office, up to £120/month
£1,000 for your home office set up + £500/year top-up
Annual team offsite to sunny spots (last ones were in Spain and Portugal ☀️)
Join one of Europe’s fastest-growing startups
Work with a veteran team of ex-employees of Google, Microsoft, Oracle, Coinbase, JP Morgan and more
Health, fitness and gift card discounts
Cycle2Work and Electric Cars scheme
Hybrid working friendly - typically 2 days/week in our London office. We’re open to discussing flexible arrangements—please share any preferences in your application

ATS Keywords

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Hard Skills & Tools

AWS securityIAMKMSnetworkingGuardDutyTypeScriptPythonGoOWASP Top 10Infrastructure as Code (IaC)

Soft Skills

clear communicationownershipautomation biascollaborationproblem-solving

Certifications

SOC 2ISO 27001