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Leidos

Builds technology for defense and civil agencies

Security Architect

Full-TimeUpdated on 10/15/2026
$107.9k - $195.1k
Senior
Bachelor's, Master's
Brussels, Belgium
In Person
CybersecuritySecurity Engineering & Architecture

About the job

Requirements
  • NATO SECRET or national equivalent security clearance.
  • Bachelor's degree in Cybersecurity, Information Assurance, Computer Science, Systems Engineering, or a related field.
  • Strong knowledge of multi-domain security concepts, attribute-based security, and associated approaches, architectures, and technologies.
  • Hands-on experience architecting Data Centric Security and Zero Trust Architecture, preferably in a military or coalition environment.
  • At least 5 years of experience in defense security architecture, cloud security, or classified system environments.
  • Deep knowledge of cloud security, data-centric protection, encryption, Identity and Access Management and Identity, Credential, and Access Management, Zero Trust, and secure system design.
  • Experience designing architectures for cross-domain, multi-level, multi-tenant systems.
  • Knowledge of Model-Based Systems Engineering tools and modelling languages such as SysML, UML, and NAF/DoDAF/UAF frameworks.
  • Strong understanding of modelling data flows, access policies, interfaces, and trust boundaries.
  • Ability to coordinate reviews, produce documentation, and close findings with Security Accreditation Authorities.
  • Proficiency with standards including NIST 800-207, NIST 800-53, ISO 27001, CIS, and NATO cyber/INFOSEC frameworks, including STANAG 4774, STANAG 4778, STANAG 5636, and ACP 240.
  • Experience conducting risk analyses and vulnerability assessments and defining mitigations.
  • Ability to guide engineers and analysts through secure-by-design principles and model-based workflows.
Responsibilities
  • Use Model-Based Systems Engineering tools, such as Sparx Enterprise Architect, to build data-centric, security-first architecture models.
  • Develop architecture views aligned with the NATO Architecture Framework version 4, including security, system, technical standards and compliance, service-based, and data views.
  • Model security behaviours using sequences, activity flows, state machines, and dependency diagrams.
  • Trace security requirements from operational concepts through system functions, services, components, and controls.
  • Assist the programme and teammates in navigating and completing the NATO Security Accreditation process for systems on restricted and classified networks; identify compliance concerns and trade-offs and propose accreditation strategies.
  • Create the System Security Architecture Document, Security Target and Risk Assessment, Secure Configuration Baselines, Security Operating Procedures, and Security Test and Evaluation artifacts.
  • Engage directly with NATO Security Accreditation Authorities and comply with the NATO Security Directive Series, STANAGs, and FMN Baseline requirements.
  • Develop and validate a fit-for-purpose security architecture for a cloud-based solution supporting NATO missions.
  • Define and evolve security concepts and architecture for a federated, multi-domain cloud environment, using security patterns for data classification, tagging, lineage, encryption, access controls, access decision logic, and policy-based enforcement.
  • Create Zero Trust enforcement models across identity, endpoints, networks, workloads, and data.
Desired Qualifications
  • A master's degree; the preferred-degree field is not specified.
  • Expertise in Zero Trust Data Format (ZTDF).
  • Expertise with Model-Based Systems Engineering tools such as Cameo, MagicDraw, or Sparx Enterprise Architect, and NATO Architecture Framework version 4 operational, system, service, and security viewpoints.
  • Demonstrated expertise applying data-centric security principles.
  • Demonstrated experience completing NATO accreditation for classified systems.
  • Strong understanding of the NATO Data Strategy and NATO Data-Centric Reference Architecture.
  • Relevant advanced certifications, including CompTIA Security+, CISSP, CCSP, and certifications in Zero Trust, Identity, Credential, and Access Management, or cloud security.
  • Model-based engineering certifications, such as SysML or vendor Model-Based Systems Engineering training.

About the company

Leidos develops technology and runs services for defense, intelligence and civilian agencies, as well as healthcare and commercial customers. It combines software and engineering work with systems integration, building secure networks and equipment used in demanding operations. Its portfolio includes medical services, energy infrastructure design and technology that supports military missions, linking specialist businesses under one parent. Customers pay through contracts for delivered systems and services, with payment tied to labor, costs or agreed project milestones. Leidos traces its roots to a company founded in 1969 and is headquartered in Reston, Virginia.

Company Size

10,001+

Company Stage

IPO

Headquarters

Reston, Virginia

Founded

1969

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Simplify's Take

What believers are saying

  • Recognized sales are growing: Leidos reported fiscal Q2 revenue of $4.56 billion, up 7%, in August 2026.
  • Technical study gets support: Leidos lists 4,092 certification prep courses and tuition assistance for full time employees.
  • Future work includes funded contracts: Leidos reported $10.2 billion of funded backlog in August 2026.

What critics are saying

  • Federal budgets dominate demand: Leidos' February 2026 filing attributed 87% of fiscal 2025 revenue to U.S. government work.
  • Cleared cyber roles restrict access: Leidos' live Fort Meade analyst posting requires active Top Secret clearance with a polygraph.
  • Cost overruns threaten margins: firm fixed price work accounted for 43% of Leidos' fiscal 2025 revenue.

What makes Leidos unique

  • Runway capacity improves through software: Leidos and UK navigation provider NATS optimize landing spacing with Intelligent Approach.
  • Leidos reaches patients directly: its QTC medical exam business connects over 15,000 providers with more than 90 clinics.
  • Leidos builds battlefield hardware: it is the Army's prime contractor for Enduring Shield, a mobile air-defense launcher.

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Benefits

Medical, dental, & vision insurance

Health Savings account

Income protection

PTO

Paid parental leave

Jury duty pay

Bereavement leave

401(k) Retirement Plan

Employee Stock Purchase Plan

Family Benefits

Growth & Insights and Company News

Headcount

6 month growth

8%

1 year growth

8%

2 year growth

8%
PR Newswire
Oct 14th, 2026
Leidos wins one-year MOD logistics extension to 2029, building on $508M in benefits

Leidos has won a one-year extension to its Logistics Commodities and Services Transformation (LCST) contract with the UK Ministry of Defence (MOD). The deal continues logistics support to the UK Armed Forces through June 2029. Leidos has been prime contractor since 2015. It manages more than 70,000 commodity NATO Stock Numbers, supports distribution to more than 600 locations worldwide, and runs the £83 million Defence Fulfilment Centre at MOD Donnington. The company estimates it has delivered £400 million in benefits to the MOD. During the extension, Leidos will work on supply chain resilience, inventory visibility, and digital capability. The programme supported the MOD through the COVID-19 pandemic and urgent needs related to Ukraine.

INSURASALES
Oct 13th, 2026
Blackstone leads $1B financing for Analogic merger with three Leidos units

Blackstone Credit & Insurance (BXCI) is leading a $1 billion financing package for the merger of Analogic Corporation with three Leidos units: Security Enterprise Solutions, Ports & Borders, and Industrial Automation. The combined business will make imaging and detection technology for sectors such as aviation security and healthcare. BXCI is lead lender and joint lead arranger, alongside HPS, Bank of America, and Wells Fargo. Brad Colman, BXCI's head of healthcare investing, called the deal proof of its strength in building large credit strategies with flexible solutions. Analogic is based in Salem, New Hampshire. Leidos employs 50,000 people and earned $17.2 billion in fiscal 2026. BXCI managed $443 billion in assets at the end of 2025. Roughly 75% of Blackstone's credit assets are backed by institutional and insurance clients.

GFM Limited
Oct 13th, 2026
Blackstone leads $1bn private credit financing for Leidos-Analogic security merger

Blackstone is leading a $1bn private credit financing to support the combination of the security enterprise solutions businesses of Leidos Holdings and Analogic Corporation, Bloomberg reported. Blackstone Credit & Insurance is reportedly lead lender and joint lead arranger, alongside HPS Investment Partners, Bank of America, and Wells Fargo. Leidos, a listed engineering and technology services company based in Virginia, serves government and commercial clients. It generated $17.2bn in revenue in 2025. Analogic develops imaging, detection, artificial intelligence, and automation technologies. Private equity firm Altaris acquired it in a $1.1bn take-private deal in 2018. Blackstone was reportedly also among the lenders in a recent financing for Waymo, which was increased to $5bn.

PR Newswire
Oct 12th, 2026
Leidos joins US Army's Reveille Forge, a "permanent hackathon" for early tech integration testing

Leidos is taking part in Reveille Forge, the US Army's new permanent integration and testing environment, to help spot technology integration problems sooner. The Army set up the site after its Operation Jailbreak exercise earlier this year. Reveille Forge replaces periodic events with a continuous "integrate-first" approach. Government, industry, and academia can test how technologies work together before they reach soldiers in the field. Leidos recently completed Jailbreak Sprint 1.5 at Redstone Arsenal in Alabama. It followed the first sprint at Fort Carson, Colorado, in June, where the company tested its IFPC Inc 2, MXR, and ALPS systems. "Now, Reveille Forge gives the Army and industry an enduring environment to integrate early, test together and mature capabilities faster," said Matt Becker, a Leidos vice president.

PR Newswire
Oct 12th, 2026
Leidos picks X-Bow to supply rocket motors for US Army's low-cost cruise missile

X-Bow Systems, a US maker of solid rocket motors, has been selected by Leidos to develop and produce booster motors for the US Army's new Low-Cost Containerized Munition (LCCM), a low-cost cruise missile. The company announced the deal on October 12, 2026, at the Association of the United States Army annual meeting in Washington. X-Bow will handle design, qualification testing, and static fires before full-rate production in 2027. Leidos will build the munitions in large quantities under the Department of War's "Arsenal of Freedom" initiative. "Modern conflict is decided by how many rounds you can put downrange, not how exquisite each one is," said chief executive officer Jason Hundley. It is the sixth new propulsion program X-Bow has won in 2026. The company recently completed its first major production contract, delivering more than 2,100 rocket motors.