Security Engineer, Senior

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. We're looking for someone who enjoys a multidisciplinary role. Security at ARQ spans Application Security, Security Operations, and Governance/Risk/Compliance, and we need someone comfortable moving across at least two of these three areas – because in a founding role, there's no one else to hand off the parts that don't fit your specialty. 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