I am developing a web application for my coworkers, and from a little management app it is becoming a more and intense large project that is involving more people as I go. I am pretty sure my boss will ask me to add even more as I will go on.
So I became unsure if I am doing things right, because I never worked on large projects (actually this is my first job).
The webapp I am working on is used by my company so I cannot do edits and changes while they are working on it; I will obviously expose them to some bugs and ux issues that could be deadly, like adding wrong data in databases etc. etc. etc.
So in the last months I "divided" my web application in two directories; one is the main index.php where they work, the other is the "development" directory, in the same server, which is only used by me.
When I finish all the edits and changes, I move everything in the development directory to the main directory used by my coworkers.
But I ask myself: is this a proper way to develop and test web apps? Lately I had been caught in terms like "continuous test driven development, unit-testing, sandbox development, etc." and moreover, making little changes in my code and uploading it every time to see what happens doesn't sound very professional to me anymore.
So how can I understand if this is a proper way to develop web applications? I am not sure even if I need all this testing, since I am the only webdev here.
I know that this can be "too broad" but I don't know any other ways to ask something like that as I know just a few things about web development in a larger scale. This is something that could be answered by a software architect for example, or a senior web dev, but I am the only web dev here.