Backend Software Engineer

We’re looking for an experienced backend engineer to help build and scale the next generation of AI-driven cybersecurity platforms at Theori. You’ll play a key role in architecting and implementing core backend systems that power Xint, our autonomous penetration testing framework. This is a foundational role in our NA engineering team—ideal for someone who thrives on solving complex systems challenges, enjoys designing for scale and reliability, and wants to help define engineering excellence in a fast-growing, AI-first company. KEY RESPONSIBILITIES • Architect, develop, and maintain backend services and APIs that power Theori’s AI security platforms. • Design for performance, scalability, and fault-tolerance across distributed systems. • Collaborate with product and frontend engineers to define and deliver secure, well-structured APIs. • Build and optimize data pipelines supporting LLM agent workflows and real-time scanning. • Establish backend best practices, coding standards, and CI/CD processes for a growing US team. • Write clean, well-tested, and maintainable code in Python and related technologies. • Mentor junior engineers and contribute to a strong, collaborative engineering culture. REQUIREMENTS • 5+ years of professional software engineering experience building production systems. • Strong proficiency in Python, with proven experience developing reliable backend services (FastAPI preferred). • Solid understanding of system design, distributed architectures, and performance optimization. • Experience with Redis, PostgreSQL, and Docker-based environments. • Familiarity with AI/LLM-driven workflows or asynchronous, event-based architectures. • Comfort working in an early-stage environment with evolving requirements. • Self-directed, ownership-oriented, and comfortable driving projects from design to deployment. • Based in US or Canada. NICE TO HAVE • Experience with Rust. • Background in cybersecurity, application security, or vulnerability analysis. • Knowledge of message queues, task orchestration, or microservices. • Familiarity with LLM integration, RAG pipelines, or vector databases. • Prior experience in startups or B2B SaaS environments. • Previous involvement in building or scaling distributed systems or engineering teams. WHAT WE OFFER Compensation & Benefits • Competitive salary + equity • Health, dental, and vision insurance • Generous PTO policy • Remote work • Laptop + home office stipend Engineering Culture • Ship features that matter • Modern Python-based stack (FastAPI, Redis, PostgreSQL, Docker) • Strong focus on testing and quality • Clear documentation and processes • Collaborative, low-ego team • Career growth and mentorship Work-Life Balance • Flexible hours, remote-first culture • Focus on outcomes, not hours