Senior GraphQL Integration Engineer / Subject Matter Expert (.NET)

Job Title: Senior GraphQL Integration Engineer / Subject Matter Expert (.NET)

Location: Washington, DC (Hybrid / Approved Remote)

Engagement Type: F ull - Time

Clearance: Able to obtain Public Trust clearance upon hire

Role Overview

Stackular is seeking a highly experienced GraphQL Integration Engineer with Subject Matter Expertise to support a federal client’s GraphQL modernization initiative. This role blends hands-on engineering execution with architectural leadership and advisory responsibilities. You will play a critical role in designing, building, and governing a federated GraphQL ecosystem while collaborating with cross-functional teams in a modern .NET-based environment.

This position is ideal for professionals who can both write production-grade code and guide architectural decisions at scale.

Key Responsibilities

Architecture & Advisory

• Provide technical leadership on GraphQL federation architecture (Apollo Federation / schema composition)
  
• Define and enforce schema governance, validation, and versioning strategies
  
• Review system architecture, APIs, and GraphQL schemas for scalability and performance
  
• Advise on API security, query optimization, and complexity management
  
• Establish and document best practices and reusable patterns
  

Engineering & Delivery

• Design and develop GraphQL subgraphs and APIs using ASP.NET Core and Hot Chocolate
  
• Implement robust data access strategies with PostgreSQL and legacy system integrations
  
• Build and deploy services in containerized environments (Docker, Kubernetes)
  
• Contribute across the full SDLC including design, development, testing, CI/CD, and deployment
  
• Collaborate in Agile teams through sprint planning, code reviews, and retrospectives
  

Integration & Operations

• Integrate GraphQL services into CI/CD pipelines (Azure DevOps, Helm)
  
• Ensure compliance with authentication and authorization standards (OAuth2, JWT, Entra)
  
• Optimize performance, observability, and reliability of GraphQL services
  
• Support integration with enterprise and legacy systems
  

Required Skills & Qualifications

For 5+ Years (Engineer Level)

• 5+ years of experience in backend/API development
  
• Strong hands-on experience with GraphQL (Apollo, Relay, etc.)
  
• Proficiency in Node.js / Java / Python
  
• Experience with REST API integration and microservices
  
• Understanding of API security (OAuth2, JWT, etc.)
  
• Familiarity with databases (SQL/NoSQL)
  
• Experience with version control (Git) and CI/CD pipelines
  

For 10+ Years (SME Level)

• 10+ years of experience in API architecture and integration
  
• Deep expertise in GraphQL design patterns, federation, and schema stitching
  
• Strong experience in enterprise architecture and distributed systems
  
• Proven ability to lead large-scale integration programs
  
• Expertise in performance tuning, scalability, and security frameworks
  
• Experience working in federal/government or compliance-heavy environments
  
• Strong stakeholder management and leadership skills
  

Nice to Have

• Experience with GraphQL Federation / Apollo Gateway
  
• Knowledge of cloud platforms (AWS, Azure, or GCP)
  
• Exposure to DevSecOps practices
  
• Familiarity with federal standards (e.g., security, accessibility, data privacy)