Sr. Web Application Developer

Leidos offers a mission-driven environment with robust benefits and continuous opportunities to innovate. This onsite Sr Web Application Developer role is based in Indiana, with a competitive annual salary ranging from USD 107,900 to 195,050. You’ll gain access to Health and Wellness programs, Income Protection, Paid Leave, and Retirement benefits to support both your professional and personal goals.

As a Senior Web Application Developer, you will lead full‑stack web solutions, AI and ML integration, client engagement, and cloud and DevOps practices across .NET/C#, JavaScript, and modern web technologies.

Responsibilities

• Own architecture, design, and development of modern web applications across .NET/C#, Node.js, and front-end frameworks like React, Angular, or Vue.
• Design and implement scalable, cloud-native solutions using microservices and serverless patterns.
• Set and promote engineering best practices, coding standards, and architectural conventions across teams.
• Build AI-enabled features, integrating with LLMs and AI APIs such as Azure OpenAI or AWS Bedrock.
• Develop intelligent search, summarization, recommendation, and automation workflows.
• Collaborate with stakeholders to identify AI opportunities that enhance user experience, decision making, or operational efficiency.
• Ensure responsible and secure use of AI technologies, focusing on data privacy, governance, and model evaluation.
• Serve as a primary technical liaison to clients, translating business needs into scalable technical solutions.
• Lead solutioning sessions, architecture discussions, and technical briefings with stakeholders.
• Provide strategic guidance on modern web technologies, cloud adoption, and AI integration.
• Build strong client relationships as a trusted technical advisor.
• Oversee development of secure, high‑performance web applications and RESTful APIs.
• Ensure interoperability and cross‑platform integration across systems.
• Drive API design, versioning, and performance optimization best practices.
• Architect and deploy applications in AWS and Azure, leveraging serverless and containerized services.
• Lead CI/CD pipeline implementation and DevSecOps practices.
• Optimize systems for scalability, reliability, and cost efficiency in cloud environments.
• Mentor developers across multiple technology stacks, beyond just .NET.
• Lead code reviews, architecture reviews, and key technical decisions.
• Foster a culture of innovation, continuous learning, and engineering excellence.
• Ensure applications meet modern security standards, including secure API design and cloud security practices.
• Implement comprehensive testing strategies and performance monitoring.
• Continuously improve system resilience, scalability, and maintainability.
• Collaborate with UI/UX teams to deliver responsive, accessible, and user-centric applications.
• Advance front‑end architecture and performance optimization techniques.
• Stay current with emerging web and AI technologies, evaluating their applicability to client missions.
• Introduce new tools, frameworks, and AI capabilities to enhance delivery and innovation.

Requirements

• US citizenship required and ability to obtain a Public Trust prior to starting.
• Bachelor’s or Master’s degree in Computer Science, Information Technology, or a related field, or equivalent experience.
• 8+ years of full‑stack web development experience, including .NET/C# and modern JavaScript frameworks.
• Demonstrated experience across multiple web technologies beyond .NET, such as Node.js or Python.
• Strong hands‑on experience with T‑SQL, including writing and optimizing queries, stored procedures, triggers, and functions.
• Proven commitment to built‑in quality, delivering reliable, maintainable, and well‑tested solutions.
• Ability to follow development best practices, perform code reviews, troubleshoot issues, and ensure quality across the lifecycle.
• Hands‑on experience integrating or developing AI/ML capabilities, including working with AI APIs (Azure OpenAI, AWS Bedrock, etc.).
• Hands‑on experience applying data‑driven or intelligent features in applications.
• Strong experience with AWS and/or Azure, including serverless architectures.
• Deep understanding of web architecture, microservices, and RESTful API design.
• Experience with SQL and NoSQL databases.
• Proven ability to lead teams and engage directly with clients.
• Strong communication skills to bridge business needs and technical solutions.
• Knowledge of secure application development and cloud security practices.

Technologies

• .NET/C#, Node.js
• React, Angular, Vue
• Python
• Azure OpenAI, AWS Bedrock
• AWS, Azure, serverless architectures
• RESTful APIs
• T-SQL, SQL, NoSQL

Benefits

• Health and Wellness programs
• Income Protection
• Paid Leave
• Retirement