I see that you’re very interested in programming and software engineering. You have already projects to show outside of the scope, and my friend, that is the best place to start specially when you’ve been learning on your own using YouTube. I’ve been in your position before many years ago, I know how tough and strange can things feel sometimes so now I’m going to share some of my knowledge that wish somebody told me sooner.
A few words on your project. I see that you have described your application before and pointed out links to go over these resources and although you did it with the best intentions, it is not possible to follow without having to spent a crazy amount of time reading the README file to start understanding what is going on. A well designed system is using an already stablished conceptual pattern that allows other people understand your code at glance. Some of these patters are Prototypes, Factory Methods, Singletons, Adapters, Bridges and many more. By using these already tested patterns you will make the application understandable by nature and very easy to test if you implement a test driven development approach that consists on automated testing using software like MochaJS.
You mentioned an audit but has anybody audit that code? I’m sure it could take them years due the spaghetti pattern. This can have disastrous implications. Do you remember Boeing 737 Max planes crashing all the time? “Spaghetti code” was the reason of it, where hundreds of lives perished very sadly.
System Design Patterns by Refactoring Guru
Test Driven Development
Microservices Architecture By Google
Domain Driven Design | Pluralsight Course (100% recommended)
NPM package manager
Remember, Don’t reinvent the wheel. Try to think if somebody already have a solution like the one you need or if its similar in any way to guide yourself during the development process.
Open WC | Web Components
Lit.dev | LitElement JS Library
Haunted | Hooks for Web Components
From all this, we have so many subjects that I’m leaving outside of the scope like infrastructure, security, reliability and scalability of the system, which each play a tremendous and important role in the availability of your system.