Full Stack Developer

Eccalon's Executives foster a supportive work environment allowing our teams to thrive, and have a fierce dedication to innovation, security, and people. Our culture is built on inclusion, teamwork, trust, and we are committed to offering career advancement opportunities to all employees. Encouraging a healthy and balanced life, we offer an extensive benefits package to support the wellness of our employees and their families. You will be joining a team of innovators, working with cutting edge technologies, supporting mission critical projects, and making an impact., Eccalon is seeking a Full Stack Developer to design, build, and ship production software across a portfolio of DoD, Intelligence, and enterprise programs. You will own features end-to-end-from React front-ends and Next.js applications through Node.js/Python APIs and AWS-hosted data stores-and actively leverage LLM and AI-assisted development techniques to accelerate delivery and enhance product capabilities. You will work closely with cross-functional teams including DevOps, UX/UI design, and program leadership in a security-conscious, compliance-driven environment., * Design, develop, and maintain full-stack web applications from UI through API to data layer, with ownership of features across the entire delivery lifecycle.

• Build front-end architecture and UI components using React and Next.js; create reusable component libraries that support consistent UX across multiple products.
• Integrate LLM and AI capabilities into product features using the Anthropic API (Claude) and other model providers; apply prompt engineering, retrieval-augmented generation (RAG), and agentic workflow patterns to build intelligent, context-aware application experiences.
• Translate designs and wireframes into high-quality, accessible, responsive code; leverage AI-assisted development tools (e.g., Claude Code) to accelerate implementation without sacrificing quality or security.
• Develop and maintain back-end services and REST APIs using Node.js and Python; design for security, scalability, and compliance from the start.
• Integrate front-end applications with back-end APIs and AWS cloud services (Cognito, Lambda, API Gateway, DynamoDB, RDS/PostgreSQL); implement authentication flows including OAuth2/OIDC and JIT provisioning.
• Implement security and data protection measures aligned to NIST 800-171 and CMMC requirements; apply OWASP Top 10 mitigations and participate in code-level security reviews.
• Implement responsive, accessible UI designs (WCAG 2.1) that render consistently across devices and browsers.
• Write clean, well-tested, and well-documented code; contribute to and enforce engineering standards through trunk-based development and peer code review.
• Conduct thorough code reviews with a focus on security, maintainability, and AI-generated code validation; mentor junior engineers on best practices.
• Troubleshoot and debug complex issues across the full stack, including integration points with LLM APIs, cloud services, and third-party authentication providers.
• Design and manage relational and NoSQL data models across PostgreSQL, DynamoDB, and MongoDB; optimize queries and data access patterns for performance and cost.
• Apply structured prompt engineering techniques-chain-of-thought, few-shot examples, tool use, and system prompt design-to build reliable, production-ready LLM-powered features; evaluate and mitigate prompt injection, hallucination, and data leakage risks.
• Partner with UX/UI designers, product managers, and DevOps to deliver features end-to-end; translate program requirements into scalable technical solutions.
• Stay current on advancements in LLM/AI tooling, web frameworks, and cloud-native development; bring new techniques back to the team through demos, documentation, and knowledge sharing.

• Bachelor's degree in Computer Science, or a related field (or equivalent work experience).
• 3+ years of experience as a Full Stack Developer shipping production web applications; experience in a DoD, federal contracting, or regulated environment a plus.
• Strong proficiency in HTML5, CSS3, JavaScript/TypeScript (ES6+), React, and Next.js; comfort building and documenting reusable component libraries.
• Proficiency in Node.js and Python for server-side development; experience with Express.js, Nest.js, and/or Next.js API routes.
• Hands-on experience integrating LLM APIs (Anthropic Claude, OpenAI, or similar) into production applications; demonstrated ability to write effective prompts, implement RAG pipelines, and build tool-use/agentic workflows.
• Experience with relational databases (PostgreSQL) and NoSQL databases (DynamoDB); comfort writing and optimizing queries and managing schema migrations.
• Solid understanding of RESTful API design, microservices architecture, and AWS services (API Gateway, Lambda, Cognito, S3, CloudFront).
• Proficiency with Git and trunk-based development workflows; experience with GitHub or GitLab for PR-based collaboration.
• Working knowledge of CI/CD pipelines (GitLab CI/CD) and cloud deployment practices on AWS; familiarity with security-focused DevSecOps gates.
• Strong analytical and problem-solving skills; ability to work independently across multiple concurrent projects and communicate technical decisions clearly to non-technical stakeholders.
• Comfort working in a regulated, compliance-aware environment; familiarity with NIST 800-171, CMMC, or FedRAMP requirements preferred.
• Strong interpersonal and communication skills; proven ability to collaborate effectively across engineering, design, DevOps, and program management teams., * Experience building AI-powered features using RAG, vector databases (e.g., pgvector, Pinecone), or LLM orchestration frameworks (e.g., LangChain, LlamaIndex).
• Familiarity with model context protocol (MCP) patterns and structured tool-use design for LLM-integrated applications.
• Experience with Azure services (Azure AD, GCC High) or AWS GovCloud in a DoD or federal contracting environment.
• Familiarity with TypeScript across both front-end and back-end (Node.js/Next.js) codebases.
• Experience with Playwright or Cypress for end-to-end testing of web applications.
• Background in UX/UI collaboration with Figma or similar design tooling.

Eccalon provides global solutions to the most challenging technological issues of the 21st-century, and our evolving portfolio spans five major markets: Machine Learning, Cybersecurity, Aerospace & Defense, Material Sciences, Advance Manufacturing, Sports Science, Biotechnology, and Health & Life Sciences. Visit our website here.