Senior Fastapi Developer Jobs in McLean, VA (NOW HIRING)

The Senior Lead Developer serves as the technical leader for enterprise application development activities supporting a Federal civilian agency's Application Development and Support Services (ADSS) program. This position leads the design, development, modernization, integration, testing, deployment, and operational support of mission-critical business applications across Microsoft 365, Azure Government, and modern cloud-native platforms.

The Senior Lead Developer provides hands-on technical leadership while mentoring development teams, establishing development standards, conducting code reviews, and ensuring software quality throughout the Agile software development lifecycle. The role is expected to balance new development with modernization of existing applications, leveraging Python, React, .NET, Microsoft Power Platform, SQL Server, PostgreSQL, and Azure cloud services. This is a hybrid position based in Washington, DC.

Key Responsibilities

Technical Leadership

• Lead software development efforts across multiple Agile development teams.
• Serve as the senior technical authority for application design and implementation.
• Establish development standards, coding guidelines, and engineering best practices.
• Mentor and coach developers through design reviews, pair programming, and technical guidance.
• Conduct peer code reviews and approve production-ready code.

Application Development

• Design, develop, test, deploy, and maintain enterprise web applications.
• Develop modern React-based user interfaces.
• Design and develop scalable Python backend services and RESTful APIs.
• Maintain and enhance existing C#/.NET applications while supporting long-term modernization initiatives.
• Develop reusable software components and shared application services.
• Integrate enterprise applications with Microsoft 365, Power Platform, Azure services, and external systems.

Cloud Modernization

• Lead migration of legacy applications to modern cloud-native architectures.
• Design scalable solutions using Azure Government services.
• Support migration from SQL Server to PostgreSQL where appropriate.
• Implement microservices, API-first architectures, and container-ready applications where applicable.
• Participate in modernization assessments and technology roadmaps.

Database Development

• Design relational database schemas.
• Develop SQL Server and PostgreSQL stored procedures, views, and optimized queries.
• Support data migration and data quality initiatives.
• Optimize application performance through database tuning.

DevSecOps

• Build and maintain CI/CD pipelines using Azure DevOps and/or GitHub.
• Implement automated builds, testing, and deployments.
• Integrate static and dynamic application security testing into development pipelines.
• Maintain Software Bills of Materials (SBOMs) for production releases.
• Support infrastructure-as-code and automated deployment practices.

Software Quality

• Develop automated unit, integration, and regression tests.
• Ensure all development complies with secure coding standards.
• Support Section 508 accessibility compliance.
• Participate in sprint planning, backlog refinement, demonstrations, and retrospectives.
• Resolve production issues and perform root cause analysis.

Security & Compliance

• Support Authority to Operate (ATO) activities.
• Remediate security vulnerabilities identified through automated scanning or penetration testing.
• Ensure compliance with:
• FISMA
• NIST SP 800-53
• Zero Trust principles
• Federal secure software development requirements
• Agency security policies

Documentation

• Produce technical design documentation.
• Maintain system architecture documentation.
• Document APIs and integration specifications.
• Develop deployment guides and operational runbooks.
• Maintain software configuration documentation.

Minimum Qualifications

• Bachelor's degree in Computer Science, Information Systems, Engineering, or related technical discipline.
• Minimum 10 years of professional software development experience.
• Minimum 5 years supporting Federal Government IT systems.
• Demonstrated experience leading software development teams.
• Experience delivering enterprise applications using Agile methodologies.
• Strong verbal and written communication skills.

Required Technical Skills

Programming Languages

• Python
• C#
• .NET
• JavaScript/TypeScript
• SQL

Front-End Technologies

• React
• HTML5
• CSS3
• Responsive web design

Backend Technologies

• Python frameworks (FastAPI, Flask, or Django)
• ASP.NET Core
• REST API development
• JSON/XML

Databases

• PostgreSQL
• Microsoft SQL Server
• Entity Framework
• Dataverse

Cloud Platforms

• Microsoft Azure
• Azure Government
• Azure App Services
• Azure Functions
• Azure Storage
• Azure Key Vault

Microsoft Technologies

• Microsoft 365
• Power Apps
• Power Automate
• Power Pages
• Power BI
• SharePoint Online
• Microsoft Teams

DevOps

• Git
• Azure DevOps
• GitHub
• CI/CD pipelines
• Automated testing
• Infrastructure as Code concepts

Preferred Qualifications

• Microsoft Certified: Azure Developer Associate
• Microsoft Certified: Azure Solutions Architect Expert
• Microsoft Power Platform Developer Associate
• Security+
• Certified Scrum Developer (CSD)
• Certified Kubernetes Application Developer (CKAD)

Preferred Experience

Experience supporting one or more of the following:

• Azure Government (GCC/GCC High)
• Microsoft Dynamics 365
• Power Platform enterprise development
• Federal cloud modernization initiatives
• Legacy application modernization
• API management platforms
• Identity and Access Management (IAM)
• OAuth/OpenID Connect
• Microservices architecture
• Containerization (Docker/Kubernetes)
• Enterprise records management systems
• Section 508 accessibility compliance
• FISMA Moderate or High systems
• Authority to Operate (ATO) support
• NIST cybersecurity controls
• DevSecOps implementation
• Enterprise CI/CD pipelines

Desired Competencies

• Technical leadership
• Software architecture
• Problem solving
• Systems integration
• Analytical thinking
• Collaboration
• Customer focus
• Continuous improvement
• Mentoring and coaching
• Strong organizational skills
• Ability to manage multiple priorities in a fast-paced Agile environment

Compensation

Salary Range: $150,000 - $162,000 annually (commensurate with experience)
Benefits: Health, dental, and vision insurance; 401(k) with employer match; paid time off; professional development opportunities.

Why Join Us?

This is an opportunity to make a direct impact on healthcare data processes that support critical regulatory functions. You will collaborate with dedicated professionals, work on meaningful projects, and contribute to improvements in public health systems.