Searching Frontend and Backend package Manager for Web Development

in the past i developed web projects that are using the same modules like the database connection class. Now I want to develop these Moduls centralized and then push them to the projects. The Moduls are developed in git repositories and mostly written in php and JavaScript.

In addition to this I want to get some other things like the newest bootstrap or jquery version.

Now I am looking for a package manager for the frontend and the backend where I can get everytime the newest version of the official projects( bootstrap e.g.) and my personal projects.