React Multi-Tenant App with SSO

I’m building a multi-tenant SaaS in React and need an experienced developer who can get an MVP online quickly. The core of the job is wiring a clean React front-end to either MongoDB or Supabase—whichever you feel will move fastest—while enforcing strict tenant isolation and modern authentication.

Authentication
• Users must be able to create an account with email/password.
• The same login screen must also offer Microsoft SSO (Azure AD OAuth2) and Google SSO.
• After a successful login, users are routed to their tenant’s sub-route or sub-domain and all subsequent API calls must respect that tenant context.

Data layer
I have no strong preference between MongoDB and Supabase; choose the one that lets you deliver the multi-tenant pattern and role-based access cleanly. If you go with Supabase, lean on row-level policies; if you choose Mongo, I expect a tidy collection strategy.

Scope of work
1. Spin up a lightweight React project (Vite or CRA is fine) with routing and protected routes.
2. Configure Microsoft and Google OAuth flows, plus traditional email sign-up/login, persisting JWT/refresh tokens securely.
3. Implement tenant creation on first sign-up and a simple switcher for users added to multiple tenants.
4. Provision the database, seed it with a sample org and user, and document local vs. production environment variables.
5. Hand over the repo and a concise README so I can run `npm install && npm start` and see a working demo.

Acceptance criteria
• New tenant self-signup creates an isolated data space.
• Existing tenant login works via email/password, Microsoft, and Google.
• Switching tenants never exposes data across boundaries.
• README explains environment setup, OAuth keys, and deployment steps.
• Delivered within the agreed ASAP timeline.

If you’ve already tackled multi-tenant auth flows, show me a code snippet or link; it will speed up hiring.