Full Stack Developer (React / .NET)

Description Xcelerate Solutions seeks a Full Stack Developer (React / .NET) to play a critical role in the sustainment, modernization, enhancement, and secure operations of enterprise mission support platforms and web-based activity reporting systems. Operating under established federal technical guidelines and Agile methodologies, the successful candidate will design, develop, test, and deploy secure, accessible, high-performing web applications. This position requires a comprehensive technical foundation in frontend development using modern JavaScript/TypeScript frameworks (specifically React.js) and backend engineering within the Microsoft .NET ecosystem (.NET Core / ASP.NET Core) backed by Microsoft SQL Server. The candidate will collaborate within a cross-functional Agile team to translate operational workflows into scalable solutions, support cloud migration activities, implement automated testing pipelines, and ensure rigorous adherence to federal cybersecurity and Section 508 accessibility baselines. Come join our award-winning organization and work with some of the most talented and brightest minds in the GovCon industry. Location: Remote Key Responsibilities The Full Stack Developer will perform the following duties: 1. Frontend & Backend Development Design, build, and maintain responsive, intuitive, and accessible user interfaces (UIs) utilizing React.js, TypeScript, JavaScript (ES6+), HTML5, CSS3/SCSS, and modern state management patterns. Develop, enhance, and maintain secure, high-performance RESTful Web APIs, business logic layers, and services using C# and .NET Core / .NET 6+. Implement and sustain modern web architecture patterns, single sign-on (SSO) authentication, and content management integration to optimize user workflows and self-service capabilities. Explore and integrate emerging capabilities, such as automated workflow enhancements and assistive logic, to streamline customer request processes and reporting workflows. 2. Database & Data Management Design, optimize, and maintain relational database schemas, tables, indexes, views, and complex stored procedures using Microsoft SQL Server (MS SQL Server). Utilize Object-Relational Mapping (ORM) frameworks (e.g., Entity Framework Core) and data access layers to ensure efficient data retrieval and persistence. Develop and maintain automated data extraction and reporting mechanisms that support real-time monitoring dashboards, KPI tracking, and ad-hoc data analysis. Assist in data modeling, data integrity verification, and database refactoring in support of ongoing cloud modernization initiatives. 3. Cloud Migration, DevSecOps & CI/CD Support the migration of enterprise applications and databases from on-premises data centers to cloud-native managed service environments. Participate in automated build, test, and deployment pipelines (CI/CD) utilizing Git-based repositories and enterprise pipeline tools (e.g., GitLab, Azure DevOps). Package and deploy application updates across multi-tier hosting environments (Development, Test/QA, Staging/Pre-Production, and Production). Provide Tier II and Tier III application and database engineering support, troubleshooting operational defects and implementing root-cause resolutions within established service level timeframes. 4. Software Quality, Testing & Accessibility Adopt an "Automation-First" and Test-Driven Development (TDD) approach, writing robust unit, integration, and end-to-end automated tests to ensure continuous quality. Ensure all web interfaces strictly comply with federal accessibility standards, including Section 508 of the Rehabilitation Act and Web Content Accessibility Guidelines (WCAG 2.1 AA). Conduct peer code reviews to enforce architectural consistency, coding standards, and maintainability. Maintain comprehensive technical documentation, including system designs, API specifications, user manuals, deployment runbooks, and Requirements Traceability Matrices (RTM). 5. Application Security & Compliance Implement secure coding fundamentals aligned with Open Worldwide Application Security Project (OWASP) standards and Application Security and Development (ASD) STIG guidelines. Remediate software vulnerabilities identified through Static Application Security Testing (SAST) and Software Composition Analysis (SCA) tools (e.g., Fortify, Sonatype). Support Risk Management Framework (RMF) activities and maintain artifact evidence to ensure continuous Authority to Operate (ATO). Assist in developing, updating, and executing Plans of Action and Milestones (POA&Ms) for technical findings and security hardening mandates. Required Qualifications Education: Bachelor’s degree in Computer Science, Information Technology, Software Engineering, or a related technical discipline (equivalent professional experience may be considered). Experience: Minimum of 5+ years of professional full-stack software development experience across the complete Software Development Life Cycle (SDLC). 3+ years of hands-on experience developing single-page applications (SPAs) and modern web components using React.js and TypeScript/JavaScript. 3+ years of experience designing, developing, and deploying backend services and RESTful APIs using C# and .NET Core / ASP.NET Core. Technical Skills: Strong working knowledge of relational database design, query optimization, and stored procedures using Microsoft SQL Server. Practical experience integrating data layers using Entity Framework Core or similar ORM frameworks. Experience with version control systems (Git), collaborative branching strategies, and issue tracking tools (e.g., Jira, GitLab). Solid understanding of web accessibility requirements (Section 508 / WCAG). Soft Skills: Strong analytical, problem-solving, and debugging skills. Proven ability to work productively within an Agile/Scrum team environment and communicate technical concepts clearly to both technical and non-technical stakeholders. Preferred Qualifications Experience refactoring legacy .NET applications and migrating workloads to secure cloud environments (e.g., Microsoft Azure Government, AWS GovCloud). Familiarity with containerization technologies (Docker) and cloud-native services. Experience integrating automated test frameworks into DevSecOps CI/CD pipelines. Knowledge of e-commerce web design principles, UI component libraries (e.g., Material-UI, Tailwind CSS, Bootstrap), and dashboard visualization tools. Experience working within federal or Department of Defense (DoD) IT environments adhering to NIST SP 800-53 controls and DISA STIG standards. Certifications 1. Cybersecurity Baseline Certification (Required) Active DoD 8570.01-M / DoD 8140 Information Assurance Technical (IAT) Level II baseline certification (or higher). Acceptable certifications include: CompTIA Security+ CE (highly preferred) GIAC Security Essentials (GSEC) Systems Security Certified Practitioner (SSCP) CCNA-Security (Or higher IAT Level III certification, such as CISSP, CASP+ CE, CCNP Security) 2. Professional / Technical Certifications (Preferred) Microsoft Certified: Azure Developer Associate Microsoft Certified: DevOps Engineer Expert Relevant React or frontend development certifications Security & Clearance Requirements Due to the secure nature of the enterprise environment and associated federal mandates: Work Status Allowable: U.S. citizenship Minimum Clearance to Start: Public Trust or Favorably Adjudicated Secret Clearance Compliance: Must strictly comply with federal cybersecurity directives, Operations Security (OPSEC) policies, and sensitive data protection requirements (PII/CUI) under the Privacy Act. About Xcelerate Solutions: Founded in 2009 and headquartered in McLean, VA, Xcelerate Solutions (www.xceleratesolutions.com) is one of America's fastest-growing companies. Xcelerate’s culture is defined by our diversified workforce of dynamic and versatile professionals, supported with growth and development opportunities that contribute to individual and company growth. This strong commitment to our employees has been recognized by our inclusion on the Washington Business Journal’s “50 Best Places to Work” list as well as being a “Great Place to Work” certified company with a 4.6 star, and a 99% CEO approval Glassdoor rating. Come find out why Xcelerate Solutions is one of the top DC Metro employers! Xcelerate Solutions is an Equal Employment Opportunity/Affirmative Action Employer. We evaluate qualified applicants without regard to race, color, national origin, religion, age, equal pay, disability, veteran status, sex, sexual orientation, gender identity, genetic information, or expression of another protected characteristic. As part of this commitment to the full inclusion of all qualified individuals, Xcelerate Solutions provides reasonable accommodation if needed because of an applicant's or an employee's disability. Pay Transparency Notice: Xcelerate Solutions will not discharge or in any other manner discriminate against employees or applicants because they have inquired about, discussed, or disclosed their own pay or the pay of another employee or applicant.