Sr. Full Stack Engineer (Top Secret Clearance Required)

i3, LLC; Huntsville (AL); On-site; USD 110,000 - 170,000; Full time

Job summary

i3, LLC is seeking a Senior Full Stack Engineer to lead design, development, and modernization of enterprise applications across the full stack—from front-end to back-end, APIs, databases, and cloud environments. The role requires collaboration with Product, DevSecOps, Cloud, Data, QA, and Migration teams to deliver secure, scalable solutions for a major federal transformation program.

The Senior Engineer will design and build REST APIs and microservices, ensure code quality and performance, and

Qualifications

• Requires 8+ years of software engineering or full-stack development experience.
• Bachelor's degree in a related field.

Responsibilities

• Design, develop, and maintain front-end and back-end components for enterprise applications.
• Build and optimize REST APIs, microservices, and system-to-system integrations.
• Collaborate across Scrum Masters, Product Leads, QA Automation Engineers, Cloud Engineers, and Data Engineers.
• Mentor mid-level engineers and support knowledge-sharing across teams.
• Ensure secure coding practices, performance tuning, and compliance with federal standards.

Skills

Full-stack development

REST APIs

Cloud environments

Security compliance

Education

Bachelor's degree

Tools

Docker

Kubernetes

Git

CI/CD

Job description

• Senior Full Stack Engineer

Position Description

i3 is seeking a Full Stack Engineer - Senior to support application design, development, integration, and modernization for a major federal transformation program. This senior role develops secure, scalable, cloud-ready solutions and works across the entire stack-front-end, back-end, APIs, databases, and cloud environments. The Full Stack Engineer collaborates with Product, DevSecOps, Cloud, Data, QA, and Migration teams to deliver mission-critical capabilities that meet federal performance, security, and compliance standards.

Your Future Duties And Responsibilities

Application & API Development

• Design, develop, and maintain front-end and back-end components for enterprise applications
• Build and optimize REST APIs, microservices, and system-to-system integrations
• Ensure code quality, performance, and maintainability across the full stack

Cloud-Ready Engineering

• Develop cloud-compatible services and applications (AWS preferred)
• Support deployment of pipelines, infrastructure integration, and CI/CD workflows
• Align application architecture with modernization and cloud migration requirements

Technical Leadership & Collaboration

• Collaborate with Scrum Masters, Product Leads, QA Automation Engineers, Cloud Engineers, and Data Engineers
• Participate in sprint planning, backlog refinement, technical design reviews, and demos
• Mentor mid-level engineers and support knowledge-sharing across teams

Security, Performance & Compliance

• Implement secure coding practices, logging, auditing, and data-handling requirements
• Conduct performance tuning, optimization, and reliability improvements
• Ensure delivery aligns with federal security standards and program governance

Testing & Quality Support

• Support automated testing and validation of application functionality and integrations
• Troubleshoot defects across the stack and coordinate with QA to resolve issues
• Validate readiness for release and major deployment events

Documentation & Reporting

• Develop technical design documents, API specifications, data flow diagrams, and code documentation
• Maintain full-stack engineering artifacts required for release, sustainment, and audits
• Provide status updates and technical insights to leadership and cross-functional teams

Required Qualifications To Be Successful In This Role

• Must have an Active Top Secret Security Clearance
• U.S. Citizenship
• Bachelor's degree and 8+ years of experience in software engineering or full-stack development
• Experience developing both front-end and back-end solutions using modern frameworks
• Hands-on experience with APIs, microservices, relational and NoSQL databases
• Experience with CI/CD pipelines, Git, DevSecOps environments, and automated testing
• Strong ability to troubleshoot issues across the entire stack
• Excellent communication and documentation skills

Preferred Qualifications

• Experience supporting DOJ, FBI, Intelligence Community, or other national-security programs
• Experience with cloud-native architectures (AWS strongly preferred)
• Familiarity with containerization (Docker), orchestration (Kubernetes), or serverless frameworks
• Experience with performance engineering, load testing, or automated quality pipelines
• Knowledge of Python, Java, JavaScript/TypeScript, or similar languages used across full-stack systems