Principal Systems Engineer (API Gateway) - TS/SCI w CI Poly
Modern Government Solutions
Job Description
Job Description
TITLE: Principal Systems Engineer (API Gateway)LOCATION: Sterling, VA (Relocation assistance considered)CLEARANCE REQUIRED: Active TS/SCI with CI PolyEMPLOYMENT TYPE: Full-time, Onsite POSITION SUMMARYModern Government Solutions (MGS) is seeking a Principal Systems Engineer to architect, integrate, and secure mission-critical API ecosystems supporting next-generation national security capabilities. In this role, you will lead the design and implementation of API gateway solutions, cloud-native integrations, and enterprise service architectures that enable secure data exchange across complex environments. Working alongside software engineers, cloud architects, cybersecurity professionals, and mission stakeholders, you will help modernize critical systems through scalable APIs, automation, and cloud technologies. The ideal candidate brings deep expertise in API platforms, cloud architecture, systems integration, and troubleshooting complex enterprise environments while maintaining the engineering rigor required to support high-impact mission operations. RESPONSIBILITIES (not limited to):Design, implement, and sustain enterprise API gateway solutions and service architectures supporting secure system integration across mission environments.Architect and support cloud-based integrations utilizing APIs, message queues, streaming platforms, ETL pipelines, and related technologies.Support Windows-based platforms, COTS applications, and cloud-hosted systems within secure enterprise environments.Troubleshoot complex application, infrastructure, and integration issues, performing root cause analysis and implementing corrective actions.Develop and execute system testing, validation, and performance assessment activities to ensure operational readiness and reliability.Collaborate with engineering, cybersecurity, infrastructure, and mission stakeholders to implement technical solutions and architectural improvements in a Scaled Agile Framework environment.Participate in Program Increment and Sprint planning, to include t-shirt sizing, story point estimation, and dependency mapping.Evaluate emerging technologies and recommend enhancements to API platforms, cloud architectures and infrastructure configurations, and enterprise integration capabilities.Create and maintain technical documentation, architecture artifacts, implementation guides, and operational procedures.Provide technical leadership and engineering guidance across API platform, cloud, and integration initiatives.Ability to remain in a stationary position for extended periods while working at a computer workstation.Ability to communicate effectively with customers, team members, and stakeholders in both written and verbal formats. REQUIRED SKILLS AND QUALIFICATIONSMust possess an active DoD TS/SCI security clearance with CI Polygraph.Must meet DoD 8140 requirements, including Security+ CE certification.Bachelor 's degree in Systems Engineering, Computer Science, Computer Engineering, Software Engineering, Information Technology, Electrical Engineering, Mathematics, Physics, or a related field.16+ years of experience designing, integrating, and supporting enterprise systems, cloud architectures, and API-driven solutions within complex mission environments.5+ years of experience implementing and administering API gateway technologies in cloud-based architectures; Experience designing secure APIs and enterprise integration solutions utilizing REST, GraphQL, event-driven architectures, message queues, streaming platforms, or ETL pipelines.Experience supporting Windows-based platforms, COTS applications, and cloud environments utilizing AWS or Azure.Experience developing software, automation, or integration solutions using Java, Python, C#, or similar programming languages, with demonstrated expertise in testing, validation, troubleshooting, root-cause analysis, and technical documentation. PREFERRED SKILLS AND QUALIFICATIONSExperience supporting Broadcom API Gateway, MuleSoft, Apigee, or similar API management platforms.Experience designing and implementing service mesh architectures utilizing Istio, Linkerd, or similar technologies.Experience optimizing cloud-hosted solutions and supporting Google Cloud Platform (GCP), Oracle Cloud Infrastructure (OCI), IBM Cloud, or similar technologies.Experience implementing ServiceNow integrations and supporting customer security requirements within classified environments.Experience supporting virtualization technologies, application streaming, cloud-native architectures, and enterprise integration platforms. *Applicants selected will be United States citizens and may be subject to a government security investigation for access to classified information.*ABOUT USAt MGS, we believe a people-first culture corresponds to organizational success through a commitment to excellence, integrity, inclusion, and an attitude that welcomes challenges meets demands, sustains growth, and drives innovation. We provide expert mission-first technical and programmatic services and solutions for the US intelligence community, the US Department of Defense, and other governmental agencies. We create people-first organizational cultures where employees feel needed in the system, not a system that needs employees. We provide you with long-term career opportunities centrally focused on our core value system: inclusion, integrity, and a commitment to excellence. MGS is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, or protected veteran status, and will not be discriminated against on the basis of disability.
$10k
...Active TS/SCI w/ CI Poly required. On-site position. Must have Sec+ or... ...+ years of experience with API gateway technologies (Broadcom API... ...development environment. Solid engineering rigor Expert... ...with Cloud architecture and system design Demonstrated experience...SuggestedFull timeContract workTemporary workImmediate startFlexible hours- ...Senior DevSecOps Engineer Location: Sterling, VA Terms: Full-Time... ...Clearance: Active DoD Top Secret TS/SCI w/CI Poly Clearance We are looking for a Sr. Systems Engineer experienced in... ...Experience with maintaining API Gateways, catalogs in a cloud-based environment...SuggestedPermanent employmentFull time
$10k
...Active TS/SCI w/ CI Poly required. On-site position. Must have Sec+ or... ...Ability to demonstrate solid engineering rigor Expert troubleshooting... ...ServiceNow or custom-built systems Knowledge of IDAM... ...Experience with maintaining API Gateways, catalogs in a cloud-based...SuggestedFull timeContract workTemporary workImmediate startFlexible hours$10k
...Active TS/SCI w/ CI Poly required. On-site position. Must have Sec+ or... ...Ability to demonstrate solid engineering rigor Expert troubleshooting... ...ServiceNow or custom-built systems Knowledge of IDAM... ...Experience with maintaining API Gateways, catalogs in a cloud-based...SuggestedFull timeContract workTemporary workImmediate startFlexible hours$10k
...Active TS/SCI w/ CI Poly required. On-site position. Must have Sec+ or better. Two (2) engineers needed. Required Education, Experience, & Skills : We are actively seeking... ...Agents (VDAs), hypervisors, and storage systems Optimize VDI performance through monitoring...SuggestedFull timeContract workTemporary workImmediate startFlexible hours- Space Systems Engineer – TS/SCI Clearance w/CI Poly Required Location Chantilly, VA Job Description Leffler Consulting is seeking a Space Systems Engineer to join our team in Chantilly, VA. Work will be performed on-site with the customer and requires an active TS/...For contractorsWork at office
- ...Description Job Description: Senior Principal Cyber Systems Engineer (DevOps Engineer)The selected... ...managed) to OCP.Only Candidates with a TS/SCI CI Poly Clearance will be consideredJob Duties... ...intermittent connectivity issues from an API Server to the Database)o Monitor (...
- ...Description TITLE: Senior Systems Engineer (IBM ELM)LOCATION: Sterling,... ...CLEARANCE REQUIRED: Active TS/SCI with CI PolyEMPLOYMENT TYPE: Full-time... ..., PowerShell, Groovy, REST APIs, and related technologies.Experience... ...-native architectures, API gateways, cross-domain solutions, and...Full timeRelocation package
- Ground Network Systems Engineer – TS/SCI Clearance w/CI Poly Required Location Chantilly, VA Job Description Leffler Consulting is seeking an experienced Ground Network Systems Engineer/Technical Advisor (SETA) with a strong background in Information Technology or Network...For contractorsWork at officeOverseas
- ...Our work depends on an Infoblox Systems Engineer joining our team to support... ...Experience with Python and APIs Self-driven, able to manage... ...skills Must have an Active TS/SCI with a willingness to obtain and maintain a CI Poly. Benefits Essential Network...Temporary workRelocation package
- ...We are seeking a hands-on Systems Engineer with deep, practical experience... ..., DynamoDB, Redis) APIs, web services, middleware, SDLC... ...PowerShell, CloudFormation) CI/CD tools (Jenkins, GitLab CI/... ...3pm Security Clearance: TS/SCI with Polygraph US Citizenship...Contract workWork experience placement
- ...details below.Maxar is hiring a Principal/Chief Engineer for a High Performance... ...products of the engineering and system administration staff over the... ...Requirements: Current/active TS/SCI security clearance and be willing and able to obtain CI polygraph. BS in Engineering...Full timeTemporary work
- ...Description Job Description Our work depends on a Systems Engineer joining our team to support Government activities... ...VDI architecture. Must possess an Active TS/SCI and willingness to obtain and maintain a CI Poly Benefits Essential Network Security (ENS) Solutions...Temporary workWork at officeRelocation package
- Cyber Systems Engineer TS/SCI CI PolyDepartment: Government Customer- ChantillyLocation: Chantilly, VATENICA is hiring a Cyber Systems Engineer.Ensures... ...communications skills.• **Must have active TS/SCI with CI Poly**• Security +, Network+, A+ requiredTENICA is an Equal...
- ...seeking a highly skilled and proactive AWS Systems Engineer to build and maintain the foundational... ...for provisioning and configuration. CI/CD & Automation: Experience building and... ..., 9am - 3pm Security Clearance: TS/SCI with Polygraph Pager duty may be required...Contract workWork experience placement
- ...Description Job Description TITLE: Sr. Systems Engineer (Citrix)LOCATION: Sterling, VA (... ...considered)CLEARANCE REQUIRED: Active TS/SCI with CI PolygraphEMPLOYMENT TYPE: Full-Time,... ...Experience integrating complex systems using APIs, message queues, and ETL pipelines. *...Full timeRelocation package
- Cyber Splunk Systems EngineerDepartment: Govt Customer-ChantillyLocation: Chantilly, VATENICA is looking to hire a Cyber Splunk Systems Engineer. Must have active TS/SCI with CI poly. Position Description:The Cyber Systems Engineer Project Management Technical Support provides...Contract workFor contractors
- ...SME Systems EngineerGCI embodies excellence, integrity... ...Software Development, Engineering, Targeting and Analysis... ...Cassandra, DynamoDB, Redis)APIs, web services,... ...PowerShell, CloudFormation)CI/CD tools (Jenkins, GitLab... ...requires an active/current TS/SCI with Polygraph...Work experience placement
- ...Job Description Job Description Systems Engineer / SME Falls Technology LLC Location: Chantilly, VA Clearance: Active TS/SCI with Polygraph required Falls Technology... ...technologies. Experience supporting CI/CD pipelines and modern software delivery...
- ...Description We are seeking one (1) Software Engineer to provide software development... ...position. Demonstrated experience with Systems Administration Demonstrated... ...Development Kits (CDK) Requirements Active TS/SCI w/ FS Poly Demonstrated experience with...
$164.38k - $274.52k
Systems Engineer SME (TS/SCI with Poly Required) Job Category: IT Infrastructure and Operations Requisition Number: SYSTE002097 Posted: May 7, 2026 Employment Type: Full-Time Work Location: On-site Salary Range: $164,382.40 USD to $274,518.40 USD Locations Herndon...Full timeWork experience placementFlexible hours$153k - $207k
...Possess: Top Secret SCI + Polygraph Clearance... ...customer requirements. TS/SCI with Polygraph is... ...operations teams (storage, systems admins, monitoring)... ...bachelor's degree in an IT or engineering related field. In lieu... ...TS/SCI with SCI Poly clearance ~ Location:...Full timeTemporary workPart timeImmediate startRemote workWorldwideFlexible hours- ...support customer requirements. TS/SCI with Polygraph is required.... ...all operations teams (storage, systems admins, monitoring) ensuring... ...’s degree in an IT or engineering related field. In lieu of a bachelor... ...lead TS/SCI with SCI Poly clearance ~ Location: At Customer...
$180k
...close-knot team of highly cleared engineers, analysts, and program... ...Looking For We are seeking an SME Systems Engineer to provide technical leadership for API Gateway technologies, cloud... ...CLEARANCE REQUIRED: TS/SCI w/ Polygraph Other Requirements...Flexible hours- Systems Engineer TS/SCI FSPDepartment: Government Customer- ChantillyLocation: Chantilly, VAACTIVE TS/SCI CLEARANCE with FS poly REQUIRED TO BE CONSIDERED FOR THIS POSITIONSystems Engineer:Enterprise... ...Bachelor's Degree Active TS/SCI w/FS PolyGeographic Location: Chantilly...For contractors
- Expert Systems Engineer - TS/SCI FSPDepartment: Government Customer - HerndonLocation: Herndon, VAACTIVE TS/SCI CLEARANCE WITH FULL SCOPE POLY REQUIRED TO BE CONSIDERED FOR THIS POSITIONPosition OverviewProvide senior-level Systems Engineering and SETA support to complex...
- ...advanced geospatial and intelligence systems in the world. You'll be exposed to,... ...Vantor is seeking a cleared Systems Engineer who is looking for an incredible challenge... ...groupsMinimum Qualifications:Active TS/SCI with ability to obtain a CI polygraph.Bachelor’s degree in...Full time
- Continuous Monitoring (ConMon) Cyber Systems EngineerDepartment: Government Customer- ChantillyLocation: Chantilly, VAPosition Description:The ConMon Cyber Engineer provides support to the customer in the area of Cyber Security. Daily tasks include, but are not limited...
$148.3k - $266.9k
...qualified candidates to fill a Principal Digital Signal Processing Engineer (DSP) positions at our... ...and maintain complex systems. We meet customer and mission... ...or related disciplineTS/SCI is requiredMinimum of 10... ...challengesAn active TS/SCI w/polygraph is preferredSecurity...Full time$170k - $185k
...PostingSterling, VA Top Secret/SCI Polygraph not... ...or less. Active TS/SCI is a must. This... ...type: Full Time W-2 or Contract Rate:... ...holidays, 401K, etc...Principal Systems Engineero... ...Model-Based Systems Engineering (MBSE) principles,... ...transferable TS/SCI with CI Polygraph.Bachelor'...Full timeContract workFor contractors
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