Demo

Senior UI/UX & API Developer

D&G Solutions
Belleville, IL Full Time
POSTED ON 10/19/2026
AVAILABLE BEFORE 10/25/2026
Hybrid | Integrated Data Environment & Global Transportation Network Convergence (IGC) | Secret Clearance Required

If you are passionate about software development, user experience, and mission-critical technology and want to help modernize transportation and logistics systems supporting the Department of Defense, we would love to talk.

Why This Role Exists

The work we do has real impact, and the people behind it matter just as much.

D&G Support Services is seeking an experienced Senior UI/UX & API Developer to support the IGC Contract's application modernization, software development, and secure delivery initiatives. In this role, you will lead the development of intuitive, accessible user interfaces and secure APIs, web services, and integration components supporting mission-critical transportation and logistics applications.

This position offers the opportunity to combine hands-on front-end development, UX design, API engineering, system integration, and technical leadership within an Agile and DevSecOps environment.

What You Will Do

  • Design, develop, test, and sustain secure, responsive, accessible web applications and reusable front-end components using JavaScript/TypeScript, HTML, CSS, and frameworks such as React, Angular, or comparable technologies.
  • Translate mission workflows and user requirements into intuitive interfaces, user flows, wireframes, prototypes, reusable components, and accessible experiences that support applicable Section 508 requirements.
  • Design, develop, test, document, and maintain RESTful APIs, web services, microservices, and integration components using Java, C#, Python, or comparable technologies; define API contracts, data models, validation rules, error handling, versioning, and interface documentation.
  • Integrate applications and APIs with relational databases, data services, analytics platforms, and existing enterprise interfaces while maintaining business rules and data integrity.
  • Implement secure authentication, authorization, role-based access, input validation, logging, auditing, and other application-security controls; troubleshoot API, integration, performance, data-mapping, and connectivity issues.
  • Develop unit, API, integration, accessibility, and automated regression tests and integrate application build, testing, security validation, and deployment activities into established GitLab CI/CD processes.
  • Support Agile delivery activities, including requirements refinement, sprint planning, demonstrations, GVT/GAT, release readiness, production support, and defect resolution.
  • Provide technical leadership through design and code reviews, mentoring, documentation, technical-debt identification, and collaboration with developers, architects, data engineers, DevSecOps, cybersecurity personnel, testers, Product Owners, functional analysts, and Government stakeholders.


Required

What We Are Looking For

  • Eight or more years of professional software-development experience, including complex enterprise web applications and system integrations.
  • Strong hands-on experience with JavaScript/TypeScript, HTML, CSS, and modern front-end frameworks such as React, Angular, or comparable technologies.
  • Experience translating functional requirements and user workflows into production-ready interfaces, reusable components, and practical UX designs.
  • Experience developing RESTful APIs, web services, microservices, and enterprise integrations using Java, C#, Python, or comparable technologies, including API contracts and documentation using OpenAPI/Swagger or similar approaches.
  • Working knowledge of relational databases, SQL, data-access patterns, and application-to-database integration.
  • Experience with Git, CI/CD, automated testing, secure coding, authentication/authorization, input validation, and application-security practices.
  • Experience developing accessible enterprise or federal web applications, including applicable Section 508 requirements.
  • Bachelor's or Master's degree in Computer Science, Cybersecurity, Data Science, Software Engineering, Information Technology, Information Systems, or a related software-engineering discipline; or one of the following certifications: FITSP-D, GCSA, GISF, or SSCP.
  • Strong technical leadership, troubleshooting, design-review, mentoring, documentation, and stakeholder-communication skills.


Preferred

  • Experience supporting U.S. Transportation Command, Department of Defense logistics, or another mission-critical federal system.
  • Experience modernizing legacy enterprise user interfaces and web services while maintaining operational continuity.
  • Experience with UX design and prototyping tools such as Figma, Adobe XD, Sketch, or comparable products.
  • Experience with enterprise identity and access management, single sign-on, and role-based access-control patterns.
  • Experience integrating applications with business-intelligence or analytics platforms such as Apache Superset.
  • Familiarity with Oracle, PostgreSQL, Amazon Aurora, Amazon RDS, or comparable relational databases.
  • Familiarity with containerized and AWS-hosted environments, DevSecOps practices, DoD Risk Management Framework, and STIG/SRG requirements.


Clearance and Eligibility

  • Active Secret security clearance or the ability to obtain and maintain one, as required by assigned duties and contract requirements.
  • This role is restricted to U.S. person(s) (U.S. citizens, permanent residents, and other protected individuals under 8 U.S.C. 1324b(a)(3)).


Location

  • Hybrid
  • Remote work may be authorized consistent with program requirements.
  • Personnel must be available for required on-site meetings, user-engagement activities, testing, demonstrations, release activities, classified-system access, or other assigned mission needs at Scott Air Force Base, Illinois.


Who We Are

At D&G Solutions, people come first; our teammates, customers, and the communities we serve. We are one of the fastest growing companies in the Washington, DC area and proud to be recognized nationally as a Best Place to Work. As an 8(a), Service Disabled Veteran Owned, and Women Owned Small Business, we bring ownership, accountability, and care to everything we do. We also deeply believe in giving back and proudly support organizations such as Homes for Our Troops, SemperK9, and Wreaths Across America.

Our teams are welcoming, collaborative, and deeply committed to mission success. We believe great work happens when people feel supported, respected, and trusted, and we work hard to create that environment every day.

What We Offer

Competitive salary | Comprehensive benefits | 401(k) | Bonus and profit sharing | Flexible hours | Education reimbursement | Generous paid time off

Final Note

If you want to work for a company that cares about its people, contribute to a mission that truly matters, and be part of a team where you are valued for who you are as well as what you do, we would love to hear from you.

Salary.com Estimation for Senior UI/UX & API Developer in Belleville, IL
$111,151 to $135,809
If your compensation planning software is too rigid to deploy winning incentive strategies, it’s time to find an adaptable solution. Compensation Planning
Enhance your organization's compensation strategy with salary data sets that HR and team managers can use to pay your staff right. Surveys & Data Sets

What is the career path for a Senior UI/UX & API Developer?

Sign up to receive alerts about other jobs on the Senior UI/UX & API Developer career path by checking the boxes next to the positions that interest you.
Income Estimation: 
$114,514 - $140,377
Income Estimation: 
$140,979 - $171,491
Income Estimation: 
$108,390 - $134,886
Income Estimation: 
$135,646 - $165,982
Employees: Get a Salary Increase
View Core, Job Family, and Industry Job Skills and Competency Data for more than 15,000 Job Titles Skills Library

Job openings at D&G Solutions

  • D&G Solutions Portsmouth, VA
  • Power Platform & SharePoint Specialist Hybrid | Portsmouth, Virginia | U.S. Citizenship Required If you are looking for meaningful work, a collaborative te... more
  • 2 Days Ago

  • D&G Solutions Arlington, VA
  • Hybrid | Arlington, VA | DHS Suitability Required If you are looking for meaningful work, a team that respects your voice, and a company that genuinely car... more
  • 3 Days Ago

  • D&G Solutions Arlington, VA
  • Public Relations/Affairs Manager Hybrid | Arlington, VA | DHS Suitability Required If you are looking for meaningful work, a team that respects your voice,... more
  • 4 Days Ago

  • D&G Solutions Belleville, IL
  • Remote / Hybrid | Integrated Data Environment & Global Transportation Network Convergence (IGC) | Secret Clearance Required If you are passionate about dat... more
  • 9 Days Ago


Not the job you're looking for? Here are some other Senior UI/UX & API Developer jobs in the Belleville, IL area that may be a better fit.

  • BJC HealthCare Saint Louis, MO
  • Additional Information About the Role BJC is hiring a UI/UX intern for our team! This position is looking for 2027-2028 grads that are majoring in User Exp... more
  • 1 Month Ago

  • Veterans United Home Loans Columbia, MO
  • Whether you come from a background in user research, interactive experience design, or a related field, you can be successful in this role. We don’t requir... more
  • 21 Days Ago

AI Assistant is available now!

Feel free to start your new journey!