I've provided all the code you need to put the pieces together quite trivially. Using go-catching, <? and the promise library (or just the core.async snippet I

I've provided all the code you need to put the pieces together quite trivially. Using go-catching, <? and the promise library (or just the core.async snippet I wrote earlier), you should be able to write the following: (go-catching (<? (async-all [asyncOpA asyncOpB asyncOpC]))) And yes, that handles errors exactly like synchronous code does. The total number of lines for implementing go-catching, <? and async-all shouldn't take more than 20-30 loc, if not less. Now, if 20-30 loc is too much for you to write, then by all means use JS.