It’s basically a packager/builder I guess. Sorry can’t advice much, because I use it only for my UXP plugins and it’s also the first time I encountered it. Managed to set it up to my needs and didn’t touch since 
BTW, it also allows a much smoother development workflow. Here’s my other post with example set-up (not full, but you should get the idea) how I use it to automate builds for local (no actual build needed), dev (basically same as prod, but can install locally) and prod (ready for Marketplace).