Senior Frontend Software Engineer, TS​/SCI CI Poly

Senior Frontend Software Engineer, TS/SCI with CI Poly - $180K-$210K + 15% 401k

Join to apply for the Senior Frontend Software Engineer role at Millennial Software.

Salary: $180,000 - $210,000 annually. Benefits include 15% 401(k) contribution, 30 days PTO, full medical/dental/vision coverage, and more.

Millennial Software is seeking a Senior Frontend Software Developer to join our collaborative team supporting a Government customer. You’ll contribute to the design, development and support of modern, data‑driven applications and tools that simplify complex user workflows and enable mission‑critical decisions.

This is a great opportunity for a motivated developer to grow technical skills across the full stack, with a particular focus on modern software development processes and technologies.

• Build and maintain web application features using modern frontend frameworks and best practices.
• Develop reusable UI components and patterns; contribute to a consistent design system.
• Ensure high‑quality user experiences through responsiveness, accessibility, and performance optimization.
• Integrate with backend APIs and collaborate on API contract design to support feature delivery.
• Write and maintain automated tests (unit, component, and end‑to‑end where applicable).
• Participate in code reviews and contribute to shared engineering standards and documentation.
• Debug and resolve frontend issues across browsers and devices; support production troubleshooting as needed.
• Improve frontend build, CI, and release processes; reduce friction for the engineering team.

• Demonstrated experience building production web applications with modern JavaScript/Type Script.
• Proficiency with at least one modern framework (e.g., React, Vue, Angular) and component‑based design patterns.
• Strong understanding of HTML, CSS, browser fundamentals, and frontend performance considerations.
• Experience integrating with APIs and managing client‑side state and data fetching patterns.
• Familiarity with testing practices (unit/component/E2E) and using Git‑based workflows.
• Ability to partner effectively with design and product, translating requirements into polished UI.
• Bachelor’s degree in a related field or equivalent practical experience.
• At least 10+ years of experience performing frontend software development.
• Active TS/SCI clearance.
• Ability to work on‑site at one of the following locations – Virginia (Fairfax, Chantilly, McLean, Sterling) or Colorado (Colorado Springs).

• Experience with accessibility standards (WCAG), inclusive design, and usability testing practices.
• Familiarity with design systems, UI tooling, and collaboration workflows (e.g., Figma handoff patterns).
• Experience with SSR/SSG frameworks (e.g., Next.js, Nuxt) and SEO/performance trade‑offs.
• Experience with observability for frontend (client‑side logging, performance monitoring, error tracking).
• Experience with micro‑frontends or large‑scale frontend architecture.
• Knowledge of secure frontend practices (XSS prevention, CSP, secure auth flows).
• Experience creating and maintaining Docker containers, Helm charts, orchestration platforms such as Kubernetes clusters, and using cloud infrastructure services (AWS/Azure/GCP).

• Employee‑owned company – equity for all employees.
• 100% company‑paid medical, dental, and vision premiums for you and all dependents.
• Ability to increase salary if you don't need medical/dental/vision coverage.
• 100% company‑paid disability and life insurance benefits.
• 15% 401(k) company contribution.
• 30 days PTO/holidays.
• Paid paternal and maternal leave.
• Generous training budget.
• Business development / growth incentives.
• Top‑notch company swag.

Millennial Software Solutions Inc. is an Equal Opportunity Employer and does not discriminate in employment on the basis of race, color, religion, sex, national origin, political affiliation, sexual orientation, gender identity, marital status, disability and genetic information, age, membership in an employee organization, or other non‑merit factors.

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