gtm.json

{
	"name": "gtm",
	"arguments": [
		"gtmId"
	],
	"snippet": "(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='{{resources.gtm}}';f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','{{settings.gtmId}}');",
	"resources": {
		"gtm": {
			"mimeType": "text/javascript",
			"url": "https://www.googletagmanager.com/gtm.js?id={{gtmId}}",
			"cacheTime": 900
		}
	}
}

snippet.js

var elm = document.createElement('div');
elm.innerHTML = 'This text was loaded through snippets';
document.body.appendChild(elm);

test.json

{
	"name": "hello",
	"arguments": [
		"hello"
	],
	"snippet": "(function() { var tag = document.createElement('script'); tag.src='{{resources.test}}'; document.body.appendChild(tag)})()",
	"resources": {
		"test": {
			"mimeType": "text/javascript",
			"url": "https://gist.githubusercontent.com/morten-olsen/da4596a115f9afd93fc1686c5460b7dd/raw/snippet.js"
		}
	}
}

validation.txt

test1234