async series

gistfile1.txt

const exec = require('child_process').exec;
var cmds = [
	'mkdir supermega',
	'echo supermega created',
	'cd supermega && mkdir wildfowl-01 wildfowl-02 wildfowl-03'];
  
(async function(){
	let heap = [];

	cmds.forEach((item, i) => {
		if(item === 'mkdir supermega'){
			heap.push(async cb => {
				return await setTimeout(async ()=>{
					await exec(item, (err, out) => {
						if(err){
							console.error(new Error(err));
							return;
						}
						out && console.log(out);
						cb();
					});
				}, 1500);
			})
		}else{
			heap.push(async cb => {
				return await exec(item, (err, out) => {
					if(err){
						console.error(new Error(err));
						return;
					}
					out && console.log(out);
					cb();
				});
			});
		}

	});

	async function run(commands){
		commands[0] && await commands[0](run.bind(null, commands.slice(1)));
	}

	run(heap);
})();

// VARIK 2

async function run(commands){
	commands[0] && await exec(commands[0], async (err, out) => {
		if(err){
			console.error(new Error(err));
			return;
		}
		out && console.log(out);
		await run(commands.slice(1));
	});
}

run(cmds);