Senior Fullstack Engineer — React/Node.js for AI Healthcare

KMS Technology, Inc.; United States; Remote; MXN 900,000 - 1,300,000; Full time

Benefits offered by this job

PTO 15 days

Family leave 5 days

Medical insurance

Annual bonus ~10%

Salary adjustment

Referral bonus

Certifications paid

Coursera license

Savings fund 5%

Grocery vouchers 5%

Job summary

KMS Technology, Inc. is seeking a Senior Fullstack Engineer in Mexico to design, develop, and maintain scalable web applications and backend services using React, TypeScript, Node.js, and NestJS.

You will work on healthcare-focused solutions, implementing secure RBAC, RESTful APIs, and AI-integrated workflows. You will contribute to frontend components, tests, documentation, and collaboration across cross-functional teams in an Agile setting, with a focus on performance, security, and

Qualifications

• 8+ years of professional software development experience in fullstack web development.
• Strong hands-on React, TypeScript, JavaScript, HTML5, and CSS3.
• Experience building backend apps and RESTful APIs with Node.js, NestJS, and TypeScript.
• Experience designing SPAs with reusable components and modular frontend architectures.
• Experience integrating RESTful APIs and handling asynchronous operations.
• Experience integrating LLM APIs and AI workflows into applications.
• Experience with Spec-Driven Development or AI-driven SDLC practices.
• Experience implementing authentication, authorization, and secure development.
• Strong understanding of software architecture and design patterns.
• Experience with automated testing (Jest, React Testing Library).
• Experience developing accessible, responsive web apps (WCAG).
• Experience with Git, GitHub, CI/CD, and code reviews.
• Familiarity with AI-assisted development tools (Claude Code, Copilot, Cursor).
• Excellent English communication; ability to work with international teams.
• Experience in Agile/Scrum environments.

Responsibilities

• Design, develop, and maintain scalable web applications using React, TypeScript, and JavaScript.
• Design, develop, and maintain scalable backend services and RESTful APIs using Node.js and NestJS.
• Develop reusable frontend components, custom hooks, and modular application architectures following modern development best practices.
• Design, develop, and integrate RESTful APIs with internal and third-party systems.
• Implement authentication, authorization, and Role-Based Access Control (RBAC) to ensure secure access to application functionality and sensitive data.
• Develop responsive, accessible, and user-friendly interfaces based on UI/UX designs and accessibility best practices.
• Collaborate with cross-functional teams to understand business requirements, technical specifications, and healthcare-related workflows.
• Write and maintain unit and integration tests to ensure application quality, reliability, and maintainability.
• Participate in code reviews, providing constructive feedback and promoting clean coding standards.
• Troubleshoot application issues, identify root causes, and implement maintainable solutions.
• Ensure sensitive healthcare information is handled securely in application code, logs, integrations, and error-handling processes.
• Take ownership of assigned features throughout the software development lifecycle, from technical design and implementation to testing and delivery.
• Create and maintain technical documentation for application components, APIs, and integrations.
• Leverage AI-assisted development tools to improve coding efficiency, code quality, and development workflows.
• Participate in Agile ceremonies, communicate development progress, and proactively identify and elevate technical risks or blockers.

Skills

React

TypeScript

JavaScript

HTML5

CSS3

SPA design

RESTful APIs

Node.js

NestJS

AI integration

Testing (Jest)

WCAG accessibility

Git

CI/CD

Agile/Scrum

English communication

Tools

Medplum

Claude Code

GitHub Copilot

Cursor

HL7 FHIR

HIPAA compliance

Job description

KMS Technology, Inc. is seeking a Senior Fullstack Engineer in Mexico to design, develop, and maintain scalable web applications and backend services using React, TypeScript, Node.js, and NestJS.

You will work on healthcare-focused solutions, implementing secure RBAC, RESTful APIs, and AI-integrated workflows. You will contribute to frontend components, tests, documentation, and collaboration across cross-functional teams in an Agile setting, with a focus on performance, security, and