Full Stack MERN Developer – Multi-Tenant SaaS Application

Posted yesterday

Worldwide

Summary

We are looking for an experienced Full Stack MERN Developer to help us build and maintain a scalable multi-tenant SaaS application. The application will allow multiple companies/organizations to use the same platform while keeping their users, data, settings, and permissions completely isolated from other tenants. Tech Stack * MongoDB * Express.js * React.js * Node.js * JavaScript / TypeScript * REST APIs * JWT Authentication * Git / GitHub * Tailwind CSS Key Responsibilities * Build and maintain a scalable MERN-based SaaS application * Implement **multi-tenant architecture** * Ensure complete data isolation between tenants * Develop secure REST APIs using Node.js and Express * Build responsive and reusable React components * Implement authentication and authorization * Develop role-based access control (RBAC) * Manage users, organizations/tenants and permissions * Design and optimize MongoDB schemas and queries * Integrate third-party APIs when required * Fix bugs and improve existing functionality * Write clean, reusable and maintainable code * Optimize application performance and scalability * Work with Git/GitHub and follow good development practices Multi-Tenant Requirements The developer should understand concepts such as: * Tenant/Organization management * Tenant-specific users and data * Data isolation * Role-based permissions * Admin and organization-level access * Tenant-aware API architecture * Secure authentication and authorization * Scalable database design Requirements * Strong experience with MongoDB, Express.js, React.js and Node.js * Previous experience building SaaS applications * Good understanding of **multi-tenant architecture** * Strong knowledge of REST APIs * Experience with JWT authentication * Experience implementing RBAC/permissions * Strong MongoDB database design skills * Good understanding of React state management * Experience working with Git/GitHub * Ability to understand an existing codebase and work independently * Strong debugging and problem-solving skills Nice to Have * Next.js * TypeScript * Redux Toolkit * PostgreSQL * Redis * Docker * AWS / Azure * Vercel / Railway * Stripe/payment integrations * CI/CD What We Are Looking For We are looking for a developer who has real-world experience building production SaaS applications, not just basic MERN CRUD projects. Please provide: 1. 2–3 relevant MERN/SaaS projects you have worked on 3. Details of any multi-tenant application you have built 4. Your experience with authentication and RBAC

  • $80.00

    Fixed-price
  • Intermediate
    Experience Level
  • Remote Job
  • Ongoing project
    Project Type
Skills and Expertise
Mandatory skills
Next.js
Tailwind CSS
React
Activity on this job
  • Proposals:20 to 50
  • Interviewing:
    0
  • Invites sent:
    0
  • Unanswered invites:
    0
About the client
Member since Mar 28, 2026
  • GBR
    London3:29 AM
  • $75 total spent
    1 hire, 0 active

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