Fullstack .NET Developer

Title: Fullstack .NET Developer
Location : Rockville, MD or McLean, VA
Target Start Date : ASAP
Type: contract
Pay Rate: DOE

We are seeking a Senior Full Stack Software Engineer to support and modernize a critical enterprise platform. This role blends legacy .NET application stewardship, modern mobile development, and cloud-native architecture.

The ideal candidate is a versatile engineer who can maintain and enhance existing .NET Framework applications while building modern mobile and cloud solutions and contributing to long-term modernization initiatives.

Core Technical Environment

.NET Full Stack Development (Primary Platform)

Backend

• .NET Framework 4.7.2, C#

• WCF Services, SOAP & REST APIs

• ASP.NET

Frontend

• ASP.NET Web Forms (.aspx), Master Pages, User Controls

• ASP.NET MVC (4.0–5.2.3), Razor

Supporting Technologies

• AJAX Control Toolkit, UpdatePanel, ScriptManager

• JavaScript, jQuery, jQuery UI, jQuery Validation

• CSS/UI: Semantic UI, jQuery UI themes, custom styles

• Reporting: ActiveReports / MESCIUS ActiveReports

• Databases: Oracle, PostgreSQL

• Messaging & Email: AWS SQS, SES

Modernization Stack (Migration Path)

• .NET Core / .NET 6

• ASP.NET Core

Mobile & Modern Frontend Development

Primary

• React Native

• JavaScript / TypeScript

Related Technologies

• Redux / Redux Toolkit

• React Navigation

• UI Libraries: React Native Paper, Native Base, React Native Elements

• Metro, Expo

• Mobile APIs (camera, geolocation, push notifications)

• Responsive cross-platform design (iOS & Android)

Bonus

• React.js / Next.js

Testing & Quality Engineering

Primary

• Selenium, Playwright

Testing Ecosystem

• Unit: xUnit, NUnit, MSTest, Jest

• Integration/E2E: Selenium, Appium, Playwright

• API Testing: Postman, SoapUI, Swagger

• Mocking: NSubstitute, Mock Service Worker, axios-mock-adapter

• Performance: JMeter, Gatling

• Code Quality & Coverage: SonarQube

Cloud & DevOps (AWS)

Required experience designing, deploying, and supporting cloud solutions using:

• EC2, ECS, Lambda

• S3, RDS, DMS

• CloudFormation

• Event-driven and scalable architectures

AI & LLM-Enabled Development (Emerging Capability)

Experience leveraging AI-assisted tools and LLM integrations to improve development workflows.

Examples

• AI code assistants (e.g., GitHub Copilot, Amazon Q Developer)

• Prompt engineering & API integrations

• Automated documentation, testing, and refactoring support

• Agentic AI or workflow automation (preferred)

Key Responsibilities

• Maintain and enhance legacy .NET Framework applications and web interfaces.

• Develop and support ASP.NET Web Forms and MVC UI components.

• Build cross-platform mobile applications using React Native.

• Design and maintain REST, SOAP, and WCF services.

• Develop and maintain reporting solutions.

• Design scalable and resilient AWS-based solutions.

• Implement automated testing across unit, integration, and E2E levels.

• Optimize application performance, security, and reliability.

• Collaborate with product, design, and engineering teams to deliver solutions.

• Participate in code reviews and engineering best practices.

• Contribute to architecture decisions and modernization strategy.

• Troubleshoot complex cross-stack technical issues.

• Improve CI/CD pipelines and DevOps practices.

Required Qualifications

• 7 years of professional software development experience

• Strong experience with .NET Framework & ASP.NET Web Forms

• Experience building MVC applications with Razor

• Proficiency in JavaScript, jQuery, and AJAX

• 3 years of React Native development experience

• Experience with automated testing frameworks

• 3 years of AWS cloud experience

• Strong understanding of software design patterns & SOLID principles

• Experience with Git-based version control

• Strong SQL and database design experience

• Experience working in Agile environments

• Excellent problem-solving and communication skills

Preferred Qualifications

• Experience modernizing legacy .NET Framework applications

• Experience with ActiveReports or similar reporting tools

• AWS certifications

• Containerization & orchestration (Docker, Kubernetes, ECS)

• Infrastructure as Code (Terraform, CloudFormation)

• Microservices & event-driven architectures

• Security best practices & OWASP guidelines

• CI/CD tooling (GitHub Actions, Jenkins)

• Monitoring & logging (CloudWatch, Splunk)

• AWS cost optimization practices

• Open-source contributions

• Bachelor's degree in Computer Science or related field (or equivalent experience)

What Success Looks Like

• Stabilizes and enhances legacy systems while enabling modernization.

• Delivers high-quality mobile and cloud-native capabilities.

• Improves performance, scalability, and reliability.

• Helps drive evolution toward modern architecture and engineering practices.

Welcome to ConsultNet, a premier national provider of technology talent and solutions. Our expertise spans across project services, contract-to-hire, direct search, and managed services onshore, nearshore, and hybrid. For over 25 years, we have connected thousands of consultants with meaningful roles through a personal, communication-driven approach, partnering with a diverse client base to build high-performing teams and create lasting impact. Our comprehensive service offerings cover a wide range of technology and engineering positions across key markets nationwide. Learn more at www.consultnet.com .

We champion equality and inclusivity, proudly supporting an Equal Opportunity Employer policy. We welcome applicants regardless of Race, Color, Religion, Sex, Sexual Orientation, Gender Identity, National Origin, Age, Genetic Information, Disability, Protected Veteran Status, or any other status protected by law.