Full-Stack Developer for StorePro POS Repair

Job Post: Full-Stack Developer Needed for Persistent Bug Fix (Replit)
Project Summary:

I need an expert full-stack developer to perform a one-time, comprehensive fix for a persistent and recurring bug in my StorePro POS application, which is hosted on Replit. I require a final, stable solution that will not introduce any new regressions.

The Problem:
My application has been experiencing the same set of critical bugs that have not been resolved by previous attempts. The issues are full-stack in nature, affecting both the front-end user experience and the back-end database operations.

Front-End Issues:
The "Sales" page catalogue shows "All Products (0)" and "No products found," despite the product database being populated.

The "Transactions" page displays a blank screen with a TypeError: m.map is not a function.

The authentication page is being bypassed, leading to incorrect user states.

Back-End Issues:
A persistent SQL syntax error in the updateProduct function prevents transactions from being completed.

The API response structure for products is being sent as an object {success: true, products: [...]} instead of a direct array, causing front-end data parsing failures.

Required Skills:
Proven expertise as a Full-Stack Software Engineer.

In-depth knowledge of React and Node.js.

Strong debugging skills with PostgreSQL and database queries (specifically fixing SQL syntax errors).

Experience with Replit and its environment is essential.

Ability to perform a comprehensive root-cause analysis and provide a permanent fix.

To Apply:
Please provide a brief summary of your relevant experience and explain your proposed approach to resolving these issues once and for all. I am looking for a reliable, expert solution.