Security Engineer, Senior

Doist; Greater London; Hybrid; GBP 26,258 - 40,846; Full time

Benefits offered by this job

Competitive salary

Stock options

Discretionary performance bonus

Latest tools & tech

World-class team

Fintech app in LATAM

Hybrid in-office (3–4 days/week)

Job summary

ARQ is seeking a Security Engineer to be the inaugural security hire and shape security locally while collaborating with a global team. You'll own security foundations, threat modelling, and cloud security across AWS and Kubernetes, with a focus on AI/agentic tools and robust incident readiness.

You will drive security initiatives, build detection rules in Datadog and CrowdStrike, and lead vendor risk assessments in a fast‑growing fintech environment. 3–4 days in‑office preferred.

Qualifications

• 4–7 years in information security, ideally shaping security at a startup or high-growth company.
• 2+ years at a regulated fintech/bank/payment company.
• Hands-on experience with cloud security (AWS, Kubernetes).
• Familiarity with application security practices: threat modelling, secure code review, CI/CD hardening, and API security testing.
• Ability to assess and secure emerging AI/agentic tooling and guardrails.
• Working knowledge of SIEM platforms and detection engineering.
• Experience with endpoint security tooling (EDR/XDR) and IAM in SaaS-heavy environments.

Responsibilities

• Drive application security initiatives: threat modelling, secure code review support, API testing, and security pipeline improvements.
• Assess and secure AI/agentic workflows, review prompts, prevent destructive actions, and control data exposure.
• Build and improve SIEM detection rules, alert pipelines, and automated response playbooks (Datadog SIEM, CrowdStrike, Cloudflare).
• Contribute to incident response readiness with IR playbooks, tabletop exercises, and forensic procedures.
• Conduct cloud security assessments across AWS and Kubernetes environments.
• Establish and run the vendor security assessment process for third‑party onboarding.

Skills

Threat modelling

Secure code review

CI/CD hardening

API security testing

Cloud security (AWS, Kubernetes)

SIEM/detection engineering

EDR/XDR security tooling

IAM in SaaS environments

Written and verbal English

Tools

Datadog SIEM

CrowdStrike

Cloudflare

Okta/Cloudflare Access

Google Workspace

Job description

What We’re Looking For

You’ll be ARQ’s first Security Engineer based in Brazil – it’s the chance to lay the foundation for how we do security in the region and shape how that function grows from here. You’ll work closely with our global security team but have real autonomy in deciding what "good" looks like locally, from day one.

What You’ll Do

• Drive application security initiatives: threat modelling, secure code review support, API testing, and security pipeline improvements
• Assess and secure AI/agentic workflows across the company—reviewing prompts, preventing destructive actions, and controlling data exposure
• Build and improve SIEM detection rules, alert pipelines, and automated response playbooks (Datadog SIEM, CrowdStrike, Cloudflare)
• Contribute to incident response readiness, including IR playbooks, tabletop exercises, and forensic procedures
• Conduct cloud security assessments across AWS and Kubernetes environments
• Establish and run the vendor security assessment process—building a scalable due diligence framework for third‑party onboarding

What You’ll Need

• 4–7 years in information security, ideally having built or significantly shaped the security function at a startup or high‑growth company – you’ve been the person who sets things up, not just maintains them
• 2+ years at a regulated fintech/bank/payment company
• Hands‑on experience with cloud infrastructure security (AWS, Kubernetes)
• Familiarity with application security practices: threat modelling, secure code review, CI/CD pipeline hardening, and API security testing
• Ability to assess and secure emerging AI/agentic tooling – you understand the risks of LLM integrations, MCP servers, and automated workflows, and can define practical guardrails
• Working knowledge of SIEM platforms and detection engineering – you’ve written detection rules
• Experience with endpoint security tooling (EDR/XDR) and identity & access management in a SaaS‑heavy environment (Google Workspace, Okta/Cloudflare Access, SSO/SCIM)
• Experience running or contributing to vendor security assessments and third‑party due diligence
• Strong written and verbal communication in English

Benefits

• Competitive salary and benefits
• Stock options, so you own part of what you build
• Discretionary performance bonus
• The latest tools and technology
• A world‑class team that will challenge and grow your skills
• The opportunity to help build the best fintech app in Latin America
• Office policy: 3‑4 days a week in‑office