It will be much easier to write a script to automate the CLI. The CLI uses the Particle build farm over the Internet to do your build and works quite well. I’d start there first.
The local build uses a local compiler tool chain and a copy of the open source repository to build entirely on your computer, no Internet required. Also, it’s how you build with develop version of the system firmware (pre-release). The instructions are here:
One of the members here wrote up something that looks pretty good for installing all of the local build tools on OS X and Linux, though I’ve never used it.