If you're using npm to run shell or node scripts, then you're running your tasks with shell or node scripts. Just because you typed "npm test" instead of "./test.sh" doesn't mean npm is doing anything to help manage your tasks.

npm (more specifically package.json) is helpful in this context for a variety of reasons:

- it's a single, central document listing your important pipelines and their purposes - anyone unfamiliar with your setup can look at the scripts property and get a very good idea very quickly

- it's auto-detected and even auto-parsed by some tools (a Ctrl-Shift-B in vscode, for example, will allow me to select a build pipeline - there's no more well-supported central format for arbitrary loose shell scripts)

- it's a consistent entry point. If you edit your npm script to point to a separate shell script, or to run webpack/whatever instead - anything external (IDEs, CI configs) pointing to npm need not change

The above are not unique to npm, but it's a well-supported, well-understood, and very simple setup that does the above.

Scripts + NPM are better together, for example because scripts executed under NPM have the local packages binaries in the path. This makes it very easy to have a fully locally installed build environment with no system dependencies. And if you do use webpack, it also helps in providing a uniform interface (Is "test" a Webpack target or a script? Who cares, just use "npm test", it'll work either way, also if we change it in the future).

And it's not an either-or case in the real world. Our company has a big Webpack config that does a lot, and still we have 15+ scripts as well (static analysis, inserting copyright headers, sourcemap uploads, 3rd party vendoring, release scripts...). Some things are better in WP (building), while some things are just simpler with a shell script.

If you're going to go to all the trouble of writing (and debugging) bash scripts, why would you not just use Grunt to do the majority of it for you?

EDIT: (Asking this in the context of the grandparent comment suggesting getting rid of build systems in favour of NPM scripts)

To clarify, I was specifically responding to the gp comment's point on needing to use one-liners in npm scripts.

The most complex "shell scripts" I've actually written for this specific purpose are simple ordered command lists, with occasional exit code checks, where appropriate. So I'm not so much talking about "writing and debugging" - this is more "replacing semicolons with newlines in a very long one-liner"

I do actually put one-liners into npm scripts instead quite often - it's a trade-off, depending on the pipeline.