React Dev for Hotel PMS SaaS Improvement

I need an experienced React + TypeScript + Supabase developer to help improve and stabilize my existing Hotel PMS SaaS called “Hotel Mantri”.

The application is already built. I do NOT want a rebuild.

Main work required:

- Fix very slow loading and performance issues
- Fix non-working sidebar buttons and navigation
- Optimize Supabase/PostgreSQL queries
- Fix React rendering / duplicate API request issues
- Improve mobile responsiveness
- Stabilize reservations, room chart, check-in/check-out, reports and housekeeping
- Help integrate Channex.io API for Channel Manager
- Implement room category mapping, rate plan mapping, inventory/rate sync, OTA reservation import, webhooks and sync logs

Tech stack:
React
TypeScript
Supabase
PostgreSQL
REST API
Webhooks

IMPORTANT:
Do not redesign or rebuild the whole software.
Existing Cash, Bank, Expense, MTD, YTD, Day Closing, Reports and Housekeeping logic must be preserved unless a confirmed bug is found.

Hindi/Hinglish communication is strongly preferred.

Before making major changes, I want a technical audit of the current application and a list of issues with estimated time and cost.