Staff / Principal Backend Software Engineer

Stack

Responsibilities

• ▹Architect and build high-throughput backend services that process real-time operational data
• ▹Lead technical design reviews and choose pragmatic approaches for new features and system improvements
• ▹Design event-driven and distributed systems that are resilient, observable, and performance-tuned
• ▹Define stable APIs for internal and external consumers, partnering with frontend for seamless integration
• ▹Improve engineering excellence through code reviews, standards, testing strategy, and incident practices
• ▹Build and maintain CI/CD workflows that enable rapid, secure delivery
• ▹Troubleshoot complex production issues, lead incident response, and drive durable fixes
• ▹Partner with product and operational stakeholders to translate needs into deliverable technical plans
• ▹Contribute to technical strategy and roadmap planning across backend services
• ▹Support hiring by participating in interviews and helping define what "great" looks like

Requirements

• ▹10+ years building scalable backend systems in production environments
• ▹4+ years of experience in Golang, or 4+ years writing server-side business logic in an object-oriented language (Java, Kotlin, C#, Python) or systems language (C, C++, Rust) with strong system design aptitude
• ▹Led technical initiatives end-to-end, including architecture, execution, and delivery
• ▹Experience designing distributed systems (e.g., event-driven architectures, messaging, consistency tradeoffs)
• ▹Built cloud-native services and operated them in production (AWS preferred)
• ▹Strong security fundamentals: secure coding, threat modeling, and defensible design choices
• ▹Track record mentoring engineers through code reviews, technical guidance, and feedback
• ▹Strong communication skills and ability to align teams around clear technical decisions

Nice to have

• ▹Experience designing data models and queries in graph databases (e.g., Neo4j, AWS Neptune)
• ▹Used relational databases (e.g., Postgres, MySQL, or MariaDB) to solve business problems, reasoning about query performance
• ▹Worked on defense, intelligence, or security-focused products with real operational users
• ▹Shipped large-scale data processing systems (streaming, near-real-time analytics, or similar)
• ▹Integrated ML/AI capabilities into production systems in a practical, measurable way
• ▹Open-source contributions or personal projects that demonstrate strong engineering craft

Soft skills

What we offer

• ▹Medical, dental, and vision plan options
• ▹Life / AD&D and disability coverage options
• ▹Paid parental leave (12 weeks for birthing parents, 4 for non-birthing parents, 6 weeks for adoptive, foster, or surrogacy parents)
• ▹Paid holidays and flexible PTO
• ▹401(k) with pre-tax and Roth options
• ▹HSA/FSA options, dependent care FSA

About the company

Founded in 2024 and headquartered in Arlington, Virginia, Twenty Technologies industrializes offensive cyber operations for the U.S. and its allies. The company has raised $138M from investors including Accel, Caffeinated Capital, Point72 Ventures, General Catalyst, and In-Q-Tel. Due to U.S. government contract and security requirements, this role is limited to U.S. citizens.