Bundler

A build tool that resolves the module graph from an entry point and emits the files a browser downloads, applying transforms along the way. It exists because thousands of small modules over the network is slower than a few large files, and because most of what you write is not directly runnable in a browser. Its configuration is where resolution, transpilation, splitting and asset handling all meet, which is why bundler config is the part of a project nobody wants to own.