Backend Software Engineer

Theori; United States; Remote; USD 140,000 - 210,000; Full time

Benefits offered by this job

Remote work

Equity

Laptop + home office stipend

Job summary

Theori is seeking an experienced backend engineer to help build and scale its AI-driven cybersecurity platforms. You’ll architect and implement core backend systems powering Xint, our autonomous penetration testing framework, and drive scale, reliability, and engineering excellence across the NA team.

Join a fast-growing AI-first company with a collaborative culture, mentoring opportunities, and a strong emphasis on testing, CI/CD, and secure APIs.

Qualifications

• 5+ years building production software systems.
• Strong Python skills; backend services, FastAPI preferred.
• Solid system design and distributed architectures experience.
• Experience with Redis, PostgreSQL, and Docker environments.
• Familiarity with AI/LLM workflows or asynchronous architectures.
• Based in US or Canada.

Responsibilities

• Architect, develop, and maintain backend services and APIs powering 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 APIs.
• Build and optimize data pipelines supporting LLM agent workflows and real-time scanning.
• Establish backend best practices, CI/CD processes for the US team.
• Write clean, well-tested, maintainable code in Python and related technologies.
• Mentor junior engineers and contribute to engineering culture.

Skills

Python

Backend design

Distributed systems

LLM workflows

Event-driven architecture

Mentoring

Ownership

Tools

Redis

PostgreSQL

Docker

FastAPI

Job description

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