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Sr. Python Developer

Concept Plus LLC

Senior Python Developer

Concept Plus is a mission-focused technology solutions provider that transforms IT concepts into impactful solutions for federal agencies. Headquartered in Fairfax, VA, we bring the agility, responsiveness, and customer intimacy of a small business combined with the quality and infrastructure of a larger firm.

Recognized as an award-winning Oracle partner, we have delivered innovative solutions across Defense, Intelligence, Civilian, Health IT, and Tribal sectors. Our highly certified experts build systems that drive efficiency, accelerate modernization, and ensure mission outcomes with certainty.

We offer competitive pay, comprehensive health, dental, and vision insurance, paid life insurance, paid time off, 11 paid holidays, performance bonuses, tuition reimbursement, unlimited training, and the opportunity to thrive in a collaborative, flexible, and innovative environment.

About the Role

Concept Plus is seeking a Senior Python Developer with 10+ years of professional development experience to support a mission-critical, enterprise-scale application operating within secure client environments, including Denied, Degraded, Intermittent, and Limited (DDIL) communication conditions. This role requires deep expertise in Python application engineering, Pyodide-based execution environments, secure coding, cloud deployment, and cross-system integration. The ideal candidate will have a strong background in DevSecOps-aligned development, Zero Trust principles, and building resilient backend services in complex, regulated environments.

What You'll Do
  • Backend Engineering (Python & Pyodide) Responsibilities:
    • Lead the ingestion, assessment, refactoring, and stabilization of complex Python codebases, including legacy system integration.
    • Design and implement secure backend services, APIs, data models, and workflow components across multiple interconnected systems.
    • Develop or support Python modules designed for execution in Pyodide environments, including WebAssembly-based packaging, secure runtime constraints, and sandboxed execution models.
    • Ensure seamless Python functionality in browser-based or lightweight execution environments where Pyodide is used to support DDIL or disconnected operations.
    • Apply secure coding standards aligned to DoD frameworks (NIST SP 800-53, 800-171, CMMC, DISA STIGs).
    • Diagnose and resolve production issues, IRs, IAVAs, performance bottlenecks, and data-related defects.
    • Drive continuous improvement of backend features, stability, security, and maintainability.
  • DevSecOps & Cloud Responsibilities:
    • Support secure CI/CD pipelines, including SAST/DAST/SCA, container scanning, and automated compliance checks.
    • Collaborate with DevSecOps teams to enable secure delivery in Cloud One or similar GovCloud environments.
    • Contribute to Continuous Monitoring (ConMon) dashboards, event tracking, logging, and cloud security posture management.
    • Maintain deployment readiness across multiple environments (development, test, staging, production).
    • Use and uphold modern Git workflows, including feature branches, PR-based code review, and secure version control.
    • Demonstrate foundational understanding of Zero Trust environments and architecture.
    • Ensure Python and Pyodide code is compatible with MosA (Modular Open Systems Approach) principles.
  • Additional Responsibilities:
    • Maintain compliance with ATO requirements, including POA&M updates, vulnerability remediation, and reporting.
    • Implement Zero Trust principles, least privilege access, and encryption controls.
    • Ensure secure handling of PII, PHI, and CUI throughout all code and data workflows.
    • Participate fully in sprint cycles: planning, backlog refinement, stand ups, reviews, and retrospectives.
    • Work within multi-vendor Agile environments, coordinating closely with government stakeholders and cross project teams.
    • Support User Assessment Events (UAEs) and contribute to human-centered design improvements.
Required Qualifications
  • US Citizen
  • Ability to obtain and/or maintain a government clearance.
  • 10+ years of Python development experience, including secure backend systems and enterprise-scale deployments.
  • Bachelors Degree
  • Proven ability to design and optimize Python code for execution in Pyodide, including performance considerations for WebAssembly-based runtimes.
  • Experience with API design, data modeling, backend architecture, and distributed workflow development.
  • Strong understanding of CI/CD pipelines, secure development practices, and cloud-native Python deployments.
  • Understanding of Zero Trust, DoD cybersecurity requirements, and secure data flow design.
  • Experience delivering production-grade capabilities in collaborative, multi-team environments.
  • Strong communication skills and the ability to articulate technical decisions to both technical and non-technical stakeholders.
  • Self-directed with strong problem-solving skills and attention to detail.
Preferred Qualifications
  • Experience with the Cloud One platform
  • Experience supporting OPMED systems · Familiarity with Defense Health Agency systems such as (OMDS, MedCOP, MHS GENESIS)
  • Experience with micro-frontend architecture
  • Familiarity with GraphQL and Apollo Client
  • Contributions to open-source projects or a demonstrable public portfolio

Concept Plus is an Equal Opportunity Employer. As such, we will give your application full consideration without regard to your race, color, religion, sex, age, national origin, disability, veteran status, sexual orientation, gender identity, or any other classification protected by federal, state, or local law.

Vacancy posted 2 days ago
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