(React + Laravel) Scale ATS SaaS from "Project level" to Enterprise/Production Level

I am building an ATS. It is still "Project Level", lacks few features, issues, problems, bugs, UI/UX issues etc. I need someone to help convert it to Production/Enterprise Level.
I'll need you to add features and integrations that other ATS are offering and we aren't but are necessary.
Improve UI/UX - even the small details that separate projects from actual SaaS.
Improve performance as much as possible using code/libraries/packages etc. (Don't ask me for upgrading hosting etc since it currently is out of budget)
Add important third-party integrations that are important.
Make the proper flow and work such that nothing breaks and if it does, we're the first ones to know and fix. It's important we know something broke before the customers, it saves the embarrassment.
Basically, convert my "Project Level" app to a "Production Level". I need you to have experience with production level stuff, not projects please.
I need you to be with me till the launch (although I will release the payment once the work is done). You'll need to work with my developer.
I know it is unrealistic to ask someone with knowledge/experience with something niche like an ATS, but I would highly prefer you if you do.
Or else, you must be willing to do heavy research about it. Try free trials of multiple ATS and see how we can be better, what all can we copy and everything else.
I need you to act as if this is your project, thus you'll be acting as a mini-CEO + developer, so you'll research recommend features, add features as I approve, make stuff better, faster, reliable and most importantly "Production Level". I hate not having the mini-details like asking confirmation before logging out, proper capitalization, proper ui/ux positioning etc etc.
If i like the work you do, then repeated hires is pretty much guaranteed, as I like to work with people repeatedly who get the work done and I form a friendly, bond with. Hopefully, if the ATS does well, then you have a place where you'll find repeated work. And who knows, if it does good, i might hire you full time/part time as soon as it starts making enough money to keep going and pay you.
I'd highly prefer if you write the bid with your own hand in detail rather than using AI.
Feel free to ask any question in the clarification board.
Also, speed is important to me. The faster the work, the better.