Find & Apply For UI / UX Designer / Developer Jobs in Belleville, Illinois

Senior

UI/UX & API

Developer 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. What We Are Looking For Required 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.

Pay:

$120,000.00 - $135,000.00 per year

Benefits:

401(k) 401(k) matching Flexible spending account Health insurance Health savings account Life insurance Paid time off Professional development assistance Referral program Retirement plan Vision insurance