Calpion - Senior Full Stack Developer - React.js/Node.js

The Role :

We're seeking a Senior Full-Stack Developer (8 Years) to lead the design and implementation of four independent React SPAs backed by Node.js microservices. You'll work alongside our AWS Solutions Architect to modernize a legacy Salesforce-based system while maintaining HIPAA compliance and zero downtime for active providers.

Required Qualifications :

• 5 years building production React applications
• 5 years building production Node.js applications (Express or similar)
• 3 years working with PostgreSQL or similar relational databases
• 2 years AWS cloud services (EC2, ECS, RDS, S3, IAM, CloudWatch)
• 2 years leading or mentoring other developers
• Proven ability to ship features end-to-end (design - deployment)
• Experience migrating legacy systems to modern architectures

Technical Stack :

• Frontend : React 18 , TypeScript, Tailwind CSS, TanStack Query, Redux/Zustand
• Backend : Node.js, Express.js, PostgreSQL, Redis
• Cloud : AWS (ECS/Fargate, RDS, S3, CloudFront, CloudWatch, SNS/SQS)
• DevOps : Docker, GitHub Actions, Terraform/CloudFormation
• Tools & Monitoring : Datadog/CloudWatch, Sentry, GitHub, Jira

Preferred Qualifications :

• Healthcare/HIPAA experience - Previous work on HIPAA-compliant systems
• Salesforce integration - Experience with Salesforce REST APIs, OAuth, JWT
• GraphQL - Query language experience
• Microservices architecture - Built or worked with microservices systems
• AWS Advanced - Lambda, SNS/SQS, Cognito, API Gateway
• Data-heavy applications - Built systems handling 100M records, complex reporting
• Claims processing - Understanding of healthcare billing, claims workflows, RCM
• ABA therapy domain - Knowledge of autism therapy, therapy management, insurance billing
• Distributed team experience - Worked across US/India time zones, asynchronous collaboration