Running bash scripts with npm

I want to try using npm to run my various build tasks for a web application. I know I can do this by adding a scripts field to my package.json like so:

"scripts": {
   "build": "some build command"
},

This gets unwieldy when you have more complex commands with a bunch of options. Is it possible to move these commands to a bash script or something along those lines? Something like:

"scripts": {
   "build": "build.sh"
},

where npm run build would execute the commands in the build.sh file?

Reading through this post it seems like it is, but I'm not clear on exactly where I'm supposed to drop my build.sh file or if I'm missing something.

Its totally possible...

"scripts": {
   "build": "./build.sh"
},

also, make sure you put a hash bang at the top of your bash file #!/usr/bin/env bash

also make sure you have permissions to execute the file

chmod +x ./build.sh

Finally, the command to run build in npm would be

npm run build

If you don't want to bother with giving permissions and the env you execute the script has for example sh, you could just do

"scripts": {
   "build": "sh ./build.sh"
}