---
title: 'Principal Engineer, Applied AI (TS/SCI) at SixGen, Inc.'
canonical: 'https://feeny.ai/job/principal-engineer-applied-ai-ts-sci-sixgen-inc-3xbd0hppqzdh'
type: 'job'
last_seen: '2026-09-07'
---

# Principal Engineer, Applied AI (TS/SCI) at SixGen, Inc.

- **Company:** SixGen, Inc.
- **Work type:** hybrid
- **Posted:** 2026-08-10
- **Last confirmed live:** 2026-09-07
- **Apply:** https://job-boards.greenhouse.io/sixgeninc/jobs/5385012008

## Job description

Principal Engineer, Applied AI

Hybrid, DMV area / Remote (with travel)

SIXGEN's mission is to deliver agile, mission-ready cybersecurity solutions that empower government and critical infrastructure organizations to stay ahead of advanced cyber threats. We combine innovation, deep expertise, and cutting-edge capabilities to uncover vulnerabilities, protect vital systems, and ensure operational superiority in an ever-evolving digital landscape.

## POSITION OVERVIEW

- Position: Principal Engineer, Applied AI
- Job Type: Full Time
- Location: Hybrid or Remote. Travel to the DMV area and customer sites may be required.
- Clearance Requirements: TS/SCI
- Travel: Up to 10%, depending on location and customer needs

## ABOUT THE TEAM

SIXGEN supports cyber and intelligence missions by helping government and commercial organizations overcome global cybersecurity challenges. Our highly skilled operators conduct research and assessments based on real-world threats, simulating adversaries and malicious actors to deliver actionable findings on critical assets and infrastructures. Our program planners advise mission owners to bring rapid solutions to intelligence leaders. Using innovative processes, tools, and techniques, we predict and overcome cybersecurity vulnerabilities.

SIXGEN is investing heavily in applied AI as a force multiplier for our engineers, operators, researchers, and customers. Our goal is not simply to incorporate AI into existing products, but to continually identify new ways that AI-native development techniques, models, agents, and automation can change how cyber capabilities are researched, built, and operated.

The Principal Engineer, Applied AI will operate at the leading edge of that effort.

This is a highly technical individual contributor role for an engineer who is comfortable working ahead of established product roadmaps and engineering patterns. The Principal Engineer will continuously evaluate emerging AI technologies, development tools, architectures, and techniques; build working prototypes; test technical assumptions; and establish viable implementation paths before larger engineering teams commit to them.

The role is intentionally exploratory. Rather than starting with a fully specified product requirement, this engineer will often begin with questions: Can this new approach materially improve how we build software? Can an agent perform this workflow reliably? Can a new model unlock a capability that was previously impractical? What would it take to operationalize this safely in a classified environment?

The Principal Engineer will turn those questions into evidence.

Success in this position means reducing technical uncertainty. The engineer will rapidly separate promising technologies from hype, demonstrate what is possible through working software, identify architectural constraints early, and hand engineering teams proven approaches they can confidently turn into durable products and mission capabilities.

## WHAT YOU'LL DO

- Explore emerging AI technologies and techniques, continuously evaluating new models, agent frameworks, developer tools, inference platforms, orchestration approaches, and AI-native software development patterns for their relevance to SIXGEN's missions and products.
- Build rapid technical prototypes, turning promising ideas into working software quickly enough to validate assumptions, expose limitations, and determine whether broader engineering investment is warranted.
- Prove technical concepts before product implementation, establishing reference architectures, integration patterns, evaluation criteria, and implementation approaches that engineering teams can build upon.
- De-risk new technology adoption, identifying performance, reliability, security, scalability, data, infrastructure, and operational constraints before they become downstream product problems.
- Advance AI-enabled software development, experimenting with coding agents, AI-assisted development environments, autonomous engineering workflows, model-driven testing, code analysis, and other techniques that can materially increase engineering velocity and capability.
- Develop AI-enabled cyber capabilities, exploring how models and autonomous systems can augment vulnerability research, reverse engineering, malware analysis, exploit development, offensive and defensive operations, and other specialized technical workflows.
- Design and evaluate agentic systems, including tool use, multi-step reasoning, memory, orchestration, human-in-the-loop controls, evaluation frameworks, and mechanisms for improving reliability in complex operational workflows.
- Create reusable technical foundations, converting successful experiments into reference implementations, libraries, patterns, technical documentation, and architectural guidance that product and engineering teams can adopt.
- Work directly with engineers and operators, identifying high-value problems where new AI capabilities can materially improve effectiveness, speed, scale, or quality.
- Transfer successful prototypes into engineering, partnering closely with product and engineering teams to ensure experimental capabilities can transition into maintainable, secure, production-quality systems.
- Establish technical evidence, not just demonstrations, developing evaluations and benchmarks that measure whether new approaches actually improve capability, reliability, cost, performance, or developer productivity.
- Challenge existing assumptions, identifying areas where AI-native architectures or development approaches may enable fundamentally different solutions rather than incremental improvements to existing systems.
- Stay deeply hands-on, writing code, integrating models and tools, designing architectures, debugging systems, running experiments, and building enough of each concept to understand how it behaves in the real world.
- Communicate findings clearly, providing engineering leadership with concise technical recommendations on what SIXGEN should adopt, continue researching, build internally, purchase, or avoid.
- Support technical demonstrations and customer engagements, particularly when emerging capabilities need to be demonstrated, evaluated, or translated into potential mission applications.
- Help shape the technical direction of applied AI at SIXGEN, serving as a trusted senior technical authority on emerging AI engineering practices and their practical application.

## REQUIRED QUALIFICATIONS

- 12+ years of experience in software engineering, cybersecurity engineering, applied research, or related technical disciplines, with significant experience operating as a senior or principal-level individual contributor.
- Exceptional hands-on software engineering ability, with a track record of rapidly designing, building, and evaluating complex technical systems.
- Demonstrated experience taking ambiguous technical ideas from initial hypothesis through working prototype and technical validation.
- Direct experience building AI-enabled applications or systems, including model integration, APIs, tool use, workflow orchestration, retrieval, evaluation, and production integration.
- Strong working knowledge of modern LLM application architectures and agentic system design, including the strengths and limitations of current models.
- Experience evaluating emerging technologies and making sound technical judgments about maturity, applicability, architectural fit, and implementation risk.
- Ability to move quickly in poorly defined problem spaces without requiring extensive product specifications or established engineering patterns.
- Strong software architecture fundamentals and the ability to distinguish between code built to answer a technical question and systems designed for long-term production use.
- Experience developing prototypes that successfully transitioned into larger engineering efforts, products, platforms, or operational capabilities.
- Ability to design meaningful experiments and evaluations rather than relying solely on qualitative demonstrations.
- Deep familiarity with at least one or more of the technical domains relevant to SIXGEN's work, such as cybersecurity, offensive security, vulnerability research, reverse engineering, malware analysis, distributed systems, developer tooling, or autonomous systems.
- Ability to communicate complex technical findings clearly to engineers, technical leadership, executives, and customers.
- Active TS/SCI clearance.
- U.S. Citizen.
- Bachelor's degree in Computer Science, Computer Engineering, Math, or a related technical field, or equivalent depth of professional experience.

## PREFERRED QUALIFICATIONS

- Experience building or evaluating autonomous or semi-autonomous systems for cybersecurity, software engineering, or other complex technical domains.
- Deep familiarity with AI-assisted software engineering tools, coding agents, development environments, and emerging approaches to AI-native software development.
- Experience with model evaluation, benchmarking, observability, and reliability testing for LLM or agent-based systems.
- Experience developing custom tools, environments, or harnesses that allow AI systems to interact with software, infrastructure, cyber tooling, or external systems.
- Familiarity with open-source and commercial model ecosystems, including model selection, inference architectures, fine-tuning, retrieval, and deployment tradeoffs.
- Experience working in research-oriented engineering organizations, advanced development groups, startups, internal incubators, or other environments where engineers are expected to rapidly explore uncertain technical opportunities.
- Background in offensive or defensive cyber operations, particularly automation of specialized technical workflows.
- Experience operating in classified or controlled environments and understanding the implications of applying modern AI technologies within those constraints.
- Familiarity with AI security, model risk, data handling, prompt injection, tool-use security, and other challenges associated with deploying AI-enabled systems in sensitive environments.
- A history of creating technical prototypes or internal tools that materially changed how an engineering organization builds software or approaches a problem.

## WHAT SUCCESS LOOKS LIKE

Within this role, success is measured less by the number of experiments performed and more by the technical leverage those experiments create.

A successful Principal Engineer, Applied AI will:

- Identify important technologies and engineering techniques before they become obvious or broadly adopted.
- Quickly determine which emerging approaches have real value for SIXGEN and which do not.
- Produce working technical evidence that allows the company to make better engineering investment decisions.
- Give product teams a substantial head start by solving difficult architectural and integration questions before full-scale development begins.
- Introduce AI-native development practices that materially improve engineering productivity and capability.
- Create prototypes that evolve into real products, internal capabilities, or customer-facing solutions.
- Continually expand what SIXGEN's engineers and operators believe is technically possible.

## COMPENSATION & BENEFITS

SIXGEN offers a competitive compensation package designed to reflect the technical depth, independence, and organizational impact expected of a Principal Engineer. Final compensation will be determined based on experience, qualifications, clearance level, and demonstrated technical capability.

Additionally, SIXGEN offers top-tier benefits for full-time employees, including:

- Employer-paid health insurance premiums (medical, dental, vision) for you and your family
- Employer-paid short/long term disability insurance and basic life/AD&D insurance
- 401K with a 4% employer contribution
- Professional development reimbursement options available (training, certification, education, etc.)
- Flexible and remote work policies for most positions
- Flexible PTO and holiday schedule

## OUR COMMITMENT

SIXGEN is an Equal Opportunity Employer. We ensure that all applicants are considered for employment without regard to race, color, religion, sexual orientation, gender identity, national origin, disability, age, marital status, ancestry, protected veteran status, or any other protected group or class.

We are committed to fostering an inclusive culture that values diversity in our people, reflecting the communities we serve and our customer base. We strive to attract and retain a diverse talent pool and create an environment where everyone is empowered to be their authentic selves at work.

## About SixGen, Inc.

## Company Overview
- **One-liner**: SIXGEN is a cybersecurity company that provides mission-aligned cyber capabilities, tools, and operations to protect government, defense, and critical infrastructure organizations from global adversaries.
- **Entity Type**: Private (acquired by Washington Harbour Partners in November 2023)
- **Headquarters**: Annapolis, Maryland, United States
- **Founded**: 2014
- **Founders**: Ethan Dietrich

## Core Business
- **Primary industry/industries**: Cybersecurity, Defense & Aerospace, Critical Infrastructure Protection
- **Target customers**: Government agencies (U.S. and allied), Defense & Aerospace contractors, Energy & Utilities, Telecommunications, Commercial Enterprises, and other Critical Infrastructure sectors (B2B, B2G)
- **Mission or purpose statement**: To reveal threats, secure operations, and empower missions. They provide the tools, automation, insights, and tradecraft needed to adapt and operate in constantly shifting threat environments with a focus on the purposeful integration of machine speed and human expertise. [sixgen.io](https://www.sixgen.io/)

## Products & Services
- **Cyber Operations Services**: Highly skilled operators conduct research, assessments, and red team operations based on real-world threats, emulating global adversaries to report detailed and actionable findings on critical assets and infrastructures.
- **Applied Research, Reverse Engineering, & RF Development**: Services that involve deep technical analysis and tool development to uncover vulnerabilities and solve complex cyber challenges.
- **Cyber Training**: Train operators to execute across the full spectrum of cyber operations.
- **Automation, AI & Data Science**: Building tools that integrate machine speed with human expertise for threat detection, data security, and scalable growth-oriented solutions.
- **Infrastructure Security**: Services focused on IT/OT visibility, proactive mitigation, automated compliance, and unified visibility for legacy and modern systems.

## Market Standing
- **Valuation/Market Cap**: Not publicly available (acquired, so no public market cap)
- **Key Metric**: Annual Revenue of **$15.3 million** | Total Funding: **$500,000** (Seed round in 2017)
- **Notable Investors/Partners**: Parent company is **Washington Harbour Partners LP** (acquired in Nov 2023). Previously acquired **Fourcast Management and Analysis** (July 2022). Board member includes **Stu Shea**.
- **Growth Signals**: 
  - Year-over-year headcount growth of **+11.7%** (currently approximately 80 employees).
  - Active job postings have increased **+87.5% year-over-year**.
  - Expanded into the United Kingdom.
  - Secured by a private equity backer, providing capital for further expansion.

## Competitive Advantages
- **Deep Government & Defense Ties**: A large portion of their workforce comes from elite government and military backgrounds (NSA, US Air Force, US Army, US Marine Corps).
- **Mission-Focused Approach**: They position themselves as a “non-traditional defense contractor” that combines innovation with deep expertise rather than bureaucratic processes.
- **Proven Track Record of Acquisitions**: The acquisition of Fourcast Management and Analysis shows their ability to integrate new capabilities and grow through M&A.
- **Full-Spectrum Cyber Operations**: They cover the entire range from offensive cyber (CNO, CNE, Red Teaming) to defensive and intelligence operations.

## Strategic Focus
- **Post-Acquisition Growth**: Under Washington Harbour Partners, the company is aggressively hiring (87.5% more job postings year-over-year) and expanding its market reach.
- **Space & Emerging Domains**: Actively hiring for roles like "Senior Intelligence & Cyber Analyst – Space Systems," indicating a push into securing space-based infrastructure.
- **Purposeful AI Integration**: Focused on integrating AI and data science not for its own sake, but to solve specific operational challenges in threat detection and automation.
- **Industry Diversification**: While rooted in defense, they are growing their commercial offerings in energy, utilities, and telecommunications.

## Why Work Here
- **Meaningful Mission**: Employees work on “missions that matter” involving national security and critical infrastructure protection against real-world adversaries.
- **Comprehensive Benefits**: 
  - **Health**: 100% paid health, dental, and vision premiums for employees and family. HRA funds up to $3,000. Coverage starts on day one.
  - **Financial**: 4% direct employer 401(k) contribution regardless of employee participation. Short/long-term disability and basic life/AD&D insurance (3x salary up to $300k).
  - **Time Off**: Flexible time off and paid holidays. Flex time allows for work-life balance across pay periods.
  - **Leave**: Parental leave, jury duty, military leave, and voting leave.
- **Professional Development**: Support for training, certifications, and conferences (DEF CON, IITSEC, etc.).
- **Culture**: Described as valuing innovation, integrity, and purpose. High percentage of technical staff (38%).
- **Work Model**: Mix of on-site (Fort Meade, Annapolis, Reston, Sterling, Huntsville, Columbia), hybrid (DMV Area), and some remote roles.
- **Compensation**: Competitive salaries; example ranges from LinkedIn data: Software Engineer ~$121,945/year, Offensive Cyber Operator ~$92,363/year.

## Sources
1. [sixgen.io](https://www.sixgen.io/)
2. [Greenhouse Jobs at SixGen, Inc.](http://job-boards.greenhouse.io/sixgeninc)
3. [SIXGEN Careers Page](https://www.sixgen.io/careers)
4. [LinkedIn Company Page - SIXGEN](https://www.linkedin.com/company/sixgenio)
5. [Tracxn Company Profile - SIXGEN](https://tracxn.com/d/companies/sixgen/__A6y0Vd77YhuDDhLrOmjxwRZ5q2qK4dqrOLR876uKVQk)

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