Lead Security Engineer

ARQ is one of the fastest-growing fintechs in the world. Our mission is to redefine how people interact with money across borders, building the infrastructure to move value seamlessly. We're still early in our journey, which means every person who joins shapes the future of our product, culture, and growth. If you're excited by big challenges, global impact, and the chance to grow fast with a world-class team, ARQ is the place to do it.

• Set the technical direction for detection engineering, alert pipelines, and automated response across the security stack (Datadog SIEM, CrowdStrike, Cloudflare), and raise the bar on how the team designs and reviews detections

• Own incident response readiness at a program level: design IR playbooks, lead tabletop exercises, and act as technical lead during major incidents

• Define DLP and data protection strategy across Google Workspace, Slack, and internal tooling, and guide the team executing it

• Set the standard and approach for cloud security assessments across AWS and Kubernetes, reviewing findings from other engineers and tackling the most complex environments directly

• Drive the application security roadmap: threat modelling standards, secure code review practices, API security testing strategy, and security pipeline architecture

• Define the company's approach to securing AI/agentic workflows – setting guardrails for prompts, destructive actions, and data exposure, and advising other teams building with LLMs/MCP servers

• Own the vendor security assessment framework itself: continuously improving the due diligence process and handling the highest-risk vendor reviews

• Act as a technical mentor to mid and senior engineers, reviewing their detection logic, assessments, and playbooks without formal management responsibilities

• 7+ years in information security, including demonstrated experience building or substantially maturing a security function or program from the ground up

• Deep, hands-on expertise in cloud infrastructure security (AWS, Kubernetes), able to architect controls

• Strong detection engineering background – you've designed detection strategy and mentored others in writing rules

• Proven experience driving application security programs: threat modelling frameworks, secure code review standards, CI/CD pipeline hardening, and API security testing strategy

• Deep experience with endpoint security tooling (EDR/XDR) and identity & access management architecture in a SaaS-heavy environment (Google Workspace, Okta/Cloudflare Access, SSO/SCIM)

• Demonstrated ability to define practical security guardrails for AI/agentic tooling – you understand the risks of LLM integrations, MCP servers, and automated workflows at an architectural level

• Experience designing or significantly evolving a vendor security assessment/third-party due diligence program

• Excellent written and verbal communication; comfortable representing security decisions to leadership and cross-functional stakeholders

• Business fluent in English

• 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