---
title: 'Staff / Principal Backend Software Engineer at Twenty'
canonical: 'https://feeny.ai/job/staff-principal-backend-software-engineer-twenty-arlington-5q4z36775w95'
type: 'job'
last_seen: '2026-09-07'
---

# Staff / Principal Backend Software Engineer at Twenty

- **Company:** Twenty
- **Location:** Arlington, VA
- **Compensation:** $192k–$455k
- **Employment:** full-time
- **Work type:** onsite
- **Posted:** 2025-08-29
- **Last confirmed live:** 2026-09-07
- **Apply:** https://jobs.ashbyhq.com/twenty/0ca195b3-a093-4f29-ba7c-b04b9ffdf873

## 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 (www.twenty.io http://www.twenty.io) industrializes offensive cyber operations for the U.S. and its allies. Headquartered in Arlington, Virginia, Twenty has raised $168M from Khosla Ventures, Accel, Caffeinated Capital, Friends & Family Capital, Point72 Ventures, General Catalyst, and In-Q-Tel.

Mission | On Site | Full Time | U.S. Citizenship Required / No Active Clearance Required

## 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.

## 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.

## 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.

## 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 built cloud-native services and operated them in production (AWS preferred).
- You have strong security fundamentals: secure coding, threat modeling, and defensible design choices.
- You have a track record mentoring engineers through code reviews, technical guidance, and feedback.
- You have strong communication skills and can align teams around clear technical decisions.

## NICE TO HAVE

- You have experience designing data models and queries in graph databases (e.g., Neo4j, AWS Neptune).
- You have used relational databases (ex: Postgres, MySQL, or MariaDB) to solve business problems and are able to reason about query performance.
- You’ve worked on defense, intelligence, or security-focused products with real operational users.
- You’ve shipped large-scale data processing systems (streaming, near-real-time analytics, or similar).
- You’ve integrated ML/AI capabilities into production systems in a practical, measurable way.
- You have open-source contributions or personal projects that demonstrate strong engineering craft.

## TECH ENVIRONMENT (YOU MIGHT WORK WITH)

- Go (Golang) business logic
- AWS and hybrid cloud/on-prem deployments
- Event-driven messaging (e.g., NATS)
- Containers and orchestration (Docker, Kubernetes)
- GraphQL and service-to-service APIs
- Graph databases (Neo4j, AWS Neptune) and complex relationship data

## Benefits

What's on the table:

- Health. Medical, dental, and vision plan options. Life / AD&D, disability coverage options.
- Family. Paid parental leave for eligible full-time employees. 12 weeks for birthing parents, 4 for non-birthing parents, 6 weeks for adoptive, foster, or intended parents through surrogacy.
- Vacation. Paid holidays and flexible PTO. Take what you need.
- Retirement. 401(k) with pre-tax and Roth options. HSA/FSA options, dependent care FSA.

Benefits vary by location, role, and eligibility. Full plan details provided during the interview and offer process.

If this role sounds like you, apply and share with us your interest

Due to U.S. government contract and security requirements, this role is limited to U.S. citizens. Some positions may also require eligibility to obtain and maintain a U.S. Government security clearance. Any active clearance requirement will be listed in the role description.

Twenty is an equal opportunity employer. We consider all qualified applicants without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, age, veteran status, disability, or any other protected status, consistent with applicable law.

If you need a reasonable accommodation during the hiring process, let us know and we will work with you.

## About Twenty

## Company Overview
- **One-liner**: Twenty builds and scales the software and capabilities of modern cyber conflict, industrializing the American arsenal for the war of now.
- **Entity Type**: Private (Series B; $138M total funding as of June 2026)
- **Headquarters**: Arlington, Virginia, United States
- **Founded**: 2024
- **Founders**: Joe Lin (CEO), Peter S., Skyler O.

## Core Business
- **Primary industry**: Cyber warfare and national security (Computer and Network Security)
- **Target customers**: U.S. military and Intelligence Community (B2G)
- **Mission**: Deliver industrial-scale cyber capabilities, ensuring the U.S. and its allies are able to deter and defeat their adversaries [twenty.io/careers](https://twenty.io/careers/).

## Products & Services
- **Cyber Warfare Platform**: Intelligent, autonomous end-to-end systems that accelerate the entire offensive cyber operations lifecycle. Encodes elite tradecraft directly into software, transforming workflows that once took weeks of manual effort into automated, continuous operations across hundreds of targets simultaneously. [twenty.io](https://twenty.io/)

## Market Standing
- **Valuation/Market Cap**: Not disclosed
- **Key Metric**: Total funding $138M (as of June 2026), including a $38M Series A led by Caffeinated Capital in November 2025 and a subsequent $100M round in June 2026 [aventure.vc](https://aventure.vc/companies/twenty-arlington-va-us) [prnewswire.com](https://www.prnewswire.com/news-releases/twenty-raises-38m-to-transform-cyber-warfare-at-industrial-scale-302622230.html)
- **Notable Investors/Partners**: Caffeinated Capital, General Catalyst, In-Q-Tel, Accel, Point72 Ventures, Friends & Family Capital [twenty.io/careers](https://twenty.io/careers/)
- **Growth Signals**: Headcount grew 245% YoY, reaching ~50 employees; 34+ active job postings as of July 2026; emerged from stealth in November 2025 with over $100M in government contracts [linkedin.com](https://www.linkedin.com/company/twentytechnologies) [prnewswire.com](https://www.prnewswire.com/news-releases/twenty-raises-38m-to-transform-cyber-warfare-at-industrial-scale-302622230.html)

## Competitive Advantages
- **Elite team**: Composed of the top 0.1% of cyber operators (from USCYBERCOM, NSA, DHS, U.S. Marine Corps, Navy, Army) and proven builders (from Palantir, Palo Alto Networks, Expanse) [twenty.io/careers](https://twenty.io/careers/)
- **Proven track record**: The founding team built the most successful SaaS cyber product in U.S. military history and defended tens of thousands of networks [twenty.io](https://twenty.io/)
- **100X improvement**: Industrial-scale automation replaces manual, bespoke methods, fundamentally reshaping how the U.S. and allies engage in cyber conflict [twenty.io](https://twenty.io/)
- **Strategic backing**: Supported by top defense-tech VCs and In-Q-Tel (the CIA’s venture arm)

## Strategic Focus
- Accelerating the delivery of intelligent, autonomous cyber warfare systems to close critical gaps in U.S. offensive capabilities
- Countering adversaries such as the People’s Republic of China (PRC) in the cyber domain
- Expanding partnerships across the U.S. military and Intelligence Community, with deployments already in active combat operations [prnewswire.com](https://www.prnewswire.com/news-releases/twenty-raises-38m-to-transform-cyber-warfare-at-industrial-scale-302622230.html)

## Why Work Here
- **Mission-driven impact**: Your code directly affects mission success or failure — “the difference between mission success and mission failure” [twenty.io/careers](https://twenty.io/careers/)
- **Elite peer group**: Work alongside top 0.1% cyber operators and world-class technologists
- **Rapid growth**: 245% headcount increase YoY; 39 open roles across engineering, product, finance, growth, and talent [twenty.io/careers](https://twenty.io/careers/)
- **Culture**: “Serious work, savage wit, zero excuses.” Emphasis on solving “crazy-hard problems” that nation-state adversaries face. “No one is coming to save us, so we’d better do it ourselves.” [twenty.io/careers](https://twenty.io/careers/)
- **Work environment**: Primarily on-site at secure locations (Arlington, VA HQ; Fort Meade, MD; San Antonio, TX; Augusta, GA). Most roles require relocation to the Washington, DC area or other government facilities. [twenty.io/careers](https://twenty.io/careers/)
- **Notable perks**: Not explicitly detailed, but the focus is on building revolutionary capabilities for national security rather than typical engagement metrics.

## Sources
1. [twenty.io](https://twenty.io/)
2. [twenty.io/careers](https://twenty.io/careers/)
3. [linkedin.com](https://www.linkedin.com/company/twentytechnologies)
4. [prnewswire.com](https://www.prnewswire.com/news-releases/twenty-raises-38m-to-transform-cyber-warfare-at-industrial-scale-302622230.html)
5. [aventure.vc](https://aventure.vc/companies/twenty-arlington-va-us)

## Other roles at Twenty

- [Accounting Manager (First Hire)](https://feeny.ai/job/accounting-manager-first-hire-twenty-arlington-j2ngp8bfzya1) — Arlington, VA
- [Senior Accountant (First Hire)](https://feeny.ai/job/senior-accountant-first-hire-twenty-arlington-at0x228y6rbj) — Arlington, VA
- [Senior / Staff Forward Deployed Software Engineer - TS/SCI Cleared](https://feeny.ai/job/senior-staff-forward-deployed-software-engineer-ts-sci-cleared-twenty-chantilly-sjhj4pgb897b) — Chantilly, VA
- [Staff Product Manager](https://feeny.ai/job/staff-product-manager-twenty-new-york-smpbxyp29dwt) — New York, NY
- [IT Security Engineer](https://feeny.ai/job/it-security-engineer-twenty-arlington-ghw0n54mkva0) — Arlington, VA
- [Director, Software Engineering](https://feeny.ai/job/director-software-engineering-twenty-arlington-x1e02f23d4cs) — Arlington, VA
- [Engineering Manager, Platform Team](https://feeny.ai/job/engineering-manager-platform-team-twenty-arlington-g1m4yknrachh) — Arlington, VA
- [Strategic Finance and Business Operations Associate (Relocation to Washington, DC)](https://feeny.ai/job/strategic-finance-and-business-operations-associate-relocation-to-washington-dc-9z8te2v40xch) — New York, NY
- [Strategic Finance and Business Operations Associate](https://feeny.ai/job/strategic-finance-and-business-operations-associate-twenty-arlington-vh3tn5y5c4n8) — Arlington, VA
- [Strategic Finance and Business Operations Associate (Relocation to Washington, DC)](https://feeny.ai/job/strategic-finance-and-business-operations-associate-relocation-to-washington-dc-n357t6m7cx5b) — San Francisco, CA