Full Stack Developer

Eccalon, LLC; Hanover (York County); On-site; USD 71,000 - 99,000; Full time

Job summary

Eccalon, LLC in Hanover, Maryland, is seeking a full‑time Full Stack Developer for an on-site role. You will work across React and Next.js front-ends with Node.js and Python APIs, leveraging AWS and other cloud services in a security-driven, regulated setting related to DoD and enterprise programs.

The role emphasizes building scalable features, integrating LLMs, applying prompt engineering and RAG workflows, and ensuring secure, compliant code through DevSecOps practices.

Qualifications

• Bachelor's degree in computer science or related field, or equivalent work experience.
• 3+ years shipping production web apps as full-stack dev; DoD/reg environments a plus.
• Strong skills in HTML5, CSS3, JavaScript/TypeScript, React, Next.js; reusable libraries.
• Proficiency in Node.js and Python; Express/Nest/Next.js API routes.
• Experience integrating LLMs via Anthropic Claude or OpenAI.
• Experience with PostgreSQL and DynamoDB; query optimization & migrations.
• Understanding REST, microservices, AWS services: API Gateway, Lambda, Cognito, S3, CloudFront.
• Git, trunk-based development; PRs via GitHub/GitLab.
• CI/CD pipelines: GitLab CI/CD, AWS deployment, DevSecOps gates.
• Familiar with NIST 800-171, CMMC, FedRAMP; strong communication skills.

Responsibilities

• Design, develop, and maintain full-stack web apps from UI to APIs and data layers.
• Build React/Next.js front-end architecture and reusable libraries.
• Integrate LLM/AI features, apply prompt engineering and RAG workflows.
• Convert designs into accessible, responsive code with AI-assisted tools.
• Develop Node.js and Python back-end services and secure REST APIs.
• Connect front-end to back-end and AWS services; implement OAuth2/OIDC.
• Apply security controls per NIST 800-171 and CMMC; participate in reviews.
• Deliver responsive, WCAG 2.1 compliant interfaces across devices.
• Write clean, tested code; uphold trunk-based development and peer reviews.
• Mentor juniors; conduct security-focused code reviews and triage issues.
• Troubleshoot complex full-stack issues including LLM integrations.
• Model data in PostgreSQL, DynamoDB, and MongoDB; optimize queries.
• Promote structured prompting and mitigate prompt injection risks.
• Partner with UX/product/DevOps to deliver end-to-end features.
• Stay current with AI tools, web frameworks, and cloud-native dev.

Skills

HTML5

CSS3

JavaScript/TypeScript

React

Next.js

Node.js

Python

Express.js

Nest.js

LLM APIs

OpenAI

Anthropic Claude

RAG

PostgreSQL

DynamoDB

MongoDB

REST API

Microservices

AWS

API Gateway

Lambda

Cognito

S3

CloudFront

Git

GitHub

GitLab

CI/CD

DevSecOps

LangChain

LlamaIndex

Azure

Playwright

Cypress

Figma

TypeScript

Web

AI

MCP

Education

Bachelor's degree in CS

Tools

GitHub

GitLab

Job description

Salary: $70,500 - 98,500 per year

Requirements:

• We require a bachelors degree in computer science or a related field, or equivalent work experience.
• We require at least 3 years of experience shipping production web applications as a full-stack developer; experience in DoD, federal contracting, or regulated environments is a plus.
• We require strong skills in HTML5, CSS3, JavaScript/TypeScript (ES6+), React, and Next.js, including building and documenting reusable component libraries.
• We require proficiency in Node.js and Python for server-side development, with experience in Express.js, Nest.js, and/or Next.js API routes.
• We require hands-on experience integrating LLM APIs such as Anthropic Claude or OpenAI into production applications, including effective prompt writing, RAG pipelines, and tool-use or agentic workflows.
• We require experience with PostgreSQL and DynamoDB, including query optimization and schema migrations.
• We require a sound understanding of REST API design, microservices, and AWS services such as API Gateway, Lambda, Cognito, S3, and CloudFront.
• We require proficiency with Git and trunk-based development, plus experience collaborating through GitHub or GitLab pull requests.
• We require working knowledge of CI/CD pipelines, including GitLab CI/CD, AWS cloud deployment, and security-focused DevSecOps gates.
• We value strong analytical and problem-solving abilities, independence across concurrent projects, and the ability to explain technical decisions clearly to non-technical stakeholders.
• We require comfort working in regulated, compliance-aware environments; familiarity with NIST 800-171, CMMC, or FedRAMP is preferred.
• We value strong communication and interpersonal skills and the ability to collaborate across engineering, design, DevOps, and program management.
• We prefer experience developing AI features with RAG, vector databases such as pgvector or Pinecone, or orchestration frameworks such as LangChain or LlamaIndex.
• We prefer familiarity with model context protocol (MCP) patterns and structured tool-use design for LLM-integrated applications.
• We prefer experience with Azure services such as Azure AD or GCC High, or AWS GovCloud in a DoD or federal contracting setting.
• We prefer TypeScript experience across both front-end and back-end Node.js/Next.js codebases.
• We prefer experience with Playwright or Cypress for end-to-end web application testing.
• We prefer experience collaborating on UX/UI using Figma or similar design tools.

Responsibilities:

• We ask you to design, develop, and maintain full-stack web applications from user interface through APIs and data layers, owning features throughout delivery.
• We expect you to build React and Next.js front-end architecture and components, including reusable libraries that provide consistent experiences across products.
• We ask you to integrate LLM and AI capabilities using Anthropic Claude and other model providers, applying prompt engineering, RAG, and agentic workflows to create context-aware features.
• We expect you to turn designs and wireframes into high-quality, accessible, responsive code, using AI-assisted tools such as Claude Code while maintaining quality and security.
• We ask you to develop and maintain Node.js and Python back-end services and REST APIs designed for security, scalability, and compliance.
• We expect you to connect front-end applications to back-end APIs and AWS services, including Cognito, Lambda, API Gateway, DynamoDB, and RDS/PostgreSQL, and implement OAuth2/OIDC authentication and JIT provisioning.
• We ask you to implement security and data-protection controls aligned with NIST 800-171 and CMMC, apply OWASP Top 10 mitigations, and participate in code-level security reviews.
• We expect you to deliver responsive, accessible interfaces meeting WCAG 2.1 and rendering consistently across devices and browsers.
• We ask you to write clean, tested, documented code and uphold engineering standards through trunk-based development and peer review.
• We expect you to conduct code reviews focused on security and maintainability, validate AI-generated code, and mentor junior engineers.
• We ask you to troubleshoot and debug complex full-stack issues, including integrations with LLM APIs, cloud services, and third-party authentication providers.
• We expect you to design and manage PostgreSQL, DynamoDB, and MongoDB data models and optimize queries and data access for performance and cost.
• We ask you to apply structured prompting methods—including chain-of-thought, few-shot examples, tool use, and system prompt design—to build reliable LLM features, while evaluating and mitigating prompt injection, hallucination, and data-leakage risks.
• We expect you to partner with UX/UI designers, product managers, and DevOps to deliver features end-to-end and turn program requirements into scalable technical solutions.
• We ask you to keep current with LLM and AI tools, web frameworks, and cloud-native development, sharing useful approaches through demonstrations, documentation, and knowledge-sharing.

Technologies:

• AI
• API
• AWS
• Lambda
• Azure
• CI/CD
• Claude Code
• Cloud
• Cypress
• DevSecOps
• DevOps
• ES6
• Figma
• Git
• GitHub
• GitLab
• HTML5
• JavaScript
• LLM
• Machine Learning
• MCP
• MongoDB
• OWASP
• Playwright
• PostgreSQL
• Python
• RAG
• REST
• React
• Security
• TypeScript
• Web
• microservices
• UX UI Design
• NodeJS
• ExpressJS
• Support
• NoSQL
• Fullstack

More:

We are Eccalon, providing global solutions to complex technology challenges across markets including machine learning, cybersecurity, aerospace and defense, material sciences, advanced manufacturing, sports science, biotechnology, and health and life sciences. We are hiring a full-time Full Stack Developer for an on-site role in Hanover, Maryland; no security clearance is required. The role supports our DoD, intelligence, and enterprise programs, working across React and Next.js applications, Node.js and Python APIs, and AWS-hosted data stores in a security-conscious, compliance-driven environment. Our executives foster a supportive culture grounded in inclusion, teamwork, trust, innovation, security, and people. We offer career advancement opportunities and an extensive benefits package supporting employee and family wellness. You will join a team of innovators using advanced technologies on mission-critical projects with meaningful impact. We provide equal employment opportunities and prohibit discrimination and harassment in accordance with applicable laws.

last updated 41 week of 2026