• Senior Back-End Developer (API-Focused)

    ManTech (Tacoma, WA)


    ManTech seeks a motivated, career-focused, and customer-oriented **Senior Back-End Developer (API-Focused)** to join an **on-site** team in either: Falls Church, VA, San Antonio, TX, Aurora, CO, or Tacoma, WA.

    Responsibilities include but are not limited to:

    + Design, implement, and maintain secure, scalable, and well-documented RESTful APIs used across multiple mobile and web applications across the Military Health System (MHS) and its global user base.

    + Provide both hands-on programming and mentorship to less experienced developers in API best practices, including service abstraction, versioning, authentication, and observability.

    + Collaborate with front-end, mobile, DevSecOps, and shared services engineers to deliver reliable and high-performance back-end services.

    + Ensure adherence to modern API design standards (OpenAPI/Swagger, consistent error handling, pagination, etc.) across legacy and greenfield applications.

    + Modernize or wrap legacy .NET, SharePoint, Sitecore, and other systems to expose data and business logic security and efficiently.

    + Develop and maintain unit, integration, and regression tests for APIs, and automate validation as part of CI/CD pipelines.

    + Support DHS’s enterprise modernization by promoting API-first thinking and reusable service patterns across development teams.

    + Actively participate in design reviews, code walkthroughs, and production readiness assessments.

    Minimum Qualifications:

    + 7+ years of progressive experience in software development with at least 2+ years focused on designing and building APIs at scale.

    + Bachelor’s degree in Computer Science, Software Engineering, Information Technology, or related discipline.

    + Proficiency in one or more server-side languages commonly used for APIs such as C#/.NET Core, Java (Spring Boot), Python (Flask/FastAPI), Node.js, or similar.

    + Strong knowledge of secure API authentication and authorization methods (OAuth 2.0, JWT, API keys, mTLS, etc.)

    + Experience designing API schemas using OpenAPI/Swagger and documenting APIs for both internal and external consumption.

    + Familiarity with modern CI/CD pipelines and containerized deployments (e.g., GitHub Actions, Jenkins, Docker).

    + Ability to analyze and refactor legacy APIs or monolithic codebases to improve modularity, performance, and maintainability.

    + Experience working with at least one RDBMS (SQL Server, PostgreSQL, Oracle, etc.) and with designing APIs around relational data models.

    + Demonstrated experience designing, deploying, and supporting APIs in both cloud-native and legacy-hybrid architectures across Azure or AWS.

    Preferred Qualifications:

    + Experience supporting Defense Health Agency (DHA), MHS, Veterans Administration (VA), or other federal health agencies.

    + Understanding of secure design principles, FedRAMP/IL4/IL5 compliance boundaries, and risk-based mitigation strategies applicable to U.S. Government healthcare environments.

    + Experience with GraphQL, gRPC, or other non-REST architectures.

    + Certifications such as AWS Certified Solutions Architect (Professional) or Azure Solutions Architect (Expert), or similar.

    + Prior experience working with user bases exceeding 10,000, preferably in contexts involving operational healthcare, clinical training, or readiness systems.

    Clearance Requirements:

    + Must be a U.S. Citizen with the ability to obtain and maintain a Public Trust clearance.

    Physical Requirements:

    + Office work, typically sedentary with some movement around the office.

    + Ability to travel (car or air) and present at conferences or meetings.

     

    ManTech International Corporation, as well as its subsidiaries proactively fulfills its role as an equal opportunity employer. We do not discriminate against any employee or applicant for employment. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, or status as a protected veteran.

     

    If you are a qualified individual with a disability and require a reasonable accommodation to apply for a position with ManTech through its online applicant system, please email us at [email protected] and provide your name and contact information.