Principal Backend Software Engineer

Position: Staff / Principal Backend Software Engineer
# Staff / Principal Backend Software Engineer Twenty Full  Time principal Arlington, Virginia, US $192k – $455k Posted 3 days ago##

Role Overview Twenty is hiring a Staff / Principal Backend Software Engineer. This is a full-time role in Arlington. Part of Twenty's Frontend hiring, posted 3 days ago. The posted range is $192k to $455k. Full responsibilities, required qualifications, and the apply link are listed in the description below.## Resume Keywords to Include Make sure these keywords appear in your resume to improve ATS scoring

Python Java Go Rust Kotlin Graph QLAWSDocker

Sign up free to auto-tailor your resume with all these keywords and get a higher ATS score## Job description

About The Company America is under sustained cyber attack. Our adversaries infiltrate our networks, steal our IP, and degrade the digital infrastructure that modern life runs on. They’ve learned—correctly—that those attacks rarely produce consequences.

Twenty was founded to change that, by making our adversaries think twice before they attack us. Our vision is American and allied primacy in cyberspace—a future where they cannot contest us, deterrence is assured, and the free world remains secure.

Founded in 2024, Twenty Technologies ((Use the "Apply for this Job" box below).) industrializes offensive cyber operations for the U.S. and its allies. Headquartered in Arlington, Virginia, Twenty has raised $138M from Accel, Caffeinated Capital, Friends & Family Capital, Point
72 Ventures, General Catalyst, and In-Q-Tel.

Role Summary You’ll design and build backend systems that turn real-time operational data into mission-critical capabilities. This role owns core services that need to be fast, reliable, and secure—operating across cloud and on-prem environments. You’ll make high-leverage architecture decisions, drive technical execution, and raise the bar through mentorship and engineering standards. You’ll partner closely with product, operations, and frontend teams to ship systems that work under real-world constraints.###

Who You Are
* You’re motivated by high-stakes, real-world outcomes—especially in national security and cyber operations.
* You take ownership: you push projects from ambiguous problem to shipped, measured capability.
* You bring calm, high-judgment leadership during incidents, tradeoff discussions, and tight timelines.
* You hold a high bar for reliability, security, and maintainability—and you help others meet it.
* You communicate clearly with both technical and non-technical partners.
* You prefer simple, scalable designs and know when complexity is justified.
* You enjoy mentoring and leveling up engineers through feedback, pairing, and strong technical direction.

What You’ll Do
* 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.

Must Have
* You have 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.
* You have led technical initiatives end-to-end, including architecture, execution, and delivery.
* You have experience designing distributed systems (e.g., event-driven architectures, messaging, consistency tradeoffs).
* You have…